diff --git a/data_acq_and_processing/common_cpp/config/include/run_config.hpp b/data_acq_and_processing/common_cpp/config/include/run_config.hpp
index b5a4af7..5342590 100644
--- a/data_acq_and_processing/common_cpp/config/include/run_config.hpp
+++ b/data_acq_and_processing/common_cpp/config/include/run_config.hpp
@@ -73,16 +73,31 @@ struct RuntimeConfig {
     std::string processing_live_config_path = "python_app/runtime/processing_live.json";
 };
 
+struct PreprocessAssetConfig {
+    std::string set_name{};
+    std::string bundle_path{};
+};
+
+struct S21PreprocessConfig {
+    PreprocessAssetConfig calibration{};
+    PreprocessAssetConfig reference{};
+};
+
+struct S11CalibrationPreprocessConfig {
+    PreprocessAssetConfig open{};
+    PreprocessAssetConfig short_standard{};
+    PreprocessAssetConfig load{};
+};
+
+struct S11PreprocessConfig {
+    S11CalibrationPreprocessConfig calibration{};
+    PreprocessAssetConfig reference{};
+};
+
 struct PreprocessConfig {
-    // Names and bundle paths selected by Python GUI layer.
-    std::string s21_calibration_set{};
-    std::string s21_reference_set{};
-    std::string s21_calibration_bundle_path{};
-    std::string s21_reference_bundle_path{};
-    std::string s11_open_calibration_bundle_path{};
-    std::string s11_short_calibration_bundle_path{};
-    std::string s11_load_calibration_bundle_path{};
-    std::string s11_reference_bundle_path{};
+    // Channel-specific preprocessing assets selected by Python GUI layer.
+    S21PreprocessConfig s21{};
+    S11PreprocessConfig s11{};
 };
 
 struct GprTxGeometry {
diff --git a/data_acq_and_processing/common_cpp/config/src/run_config.cpp b/data_acq_and_processing/common_cpp/config/src/run_config.cpp
index 7d389fe..7d9217f 100644
--- a/data_acq_and_processing/common_cpp/config/src/run_config.cpp
+++ b/data_acq_and_processing/common_cpp/config/src/run_config.cpp
@@ -140,6 +140,20 @@ using Json = nlohmann::json;
     return fallback;
 }
 
+[[nodiscard]] auto parse_preprocess_asset(
+    const Json& object,
+    const std::string& key,
+    const std::string& context
+) -> PreprocessAssetConfig {
+    const auto asset_context = context + "." + key;
+    const auto* asset_obj = as_object(required_field(object, key), asset_context);
+
+    PreprocessAssetConfig asset{};
+    asset.set_name = optional_string(*asset_obj, "set_name", "");
+    asset.bundle_path = optional_string(*asset_obj, "bundle_path", "");
+    return asset;
+}
+
 [[nodiscard]] auto parse_driver_mode(const std::string& value) -> DriverMode {
     if (value == "mock") {
         return DriverMode::Mock;
@@ -438,18 +452,20 @@ auto load_run_config(const std::string& path) -> RunConfig {
 
     {
         const auto* preprocess_obj = as_object(required_field(*root_obj, "preprocess"), "preprocess");
-        config.preprocess.s21_calibration_set = optional_string(*preprocess_obj, "s21_calibration_set", "");
-        config.preprocess.s21_reference_set = optional_string(*preprocess_obj, "s21_reference_set", "");
-        config.preprocess.s21_calibration_bundle_path =
-            optional_string(*preprocess_obj, "s21_calibration_bundle_path", "");
-        config.preprocess.s21_reference_bundle_path = optional_string(*preprocess_obj, "s21_reference_bundle_path", "");
-        config.preprocess.s11_open_calibration_bundle_path =
-            optional_string(*preprocess_obj, "s11_open_calibration_bundle_path", "");
-        config.preprocess.s11_short_calibration_bundle_path =
-            optional_string(*preprocess_obj, "s11_short_calibration_bundle_path", "");
-        config.preprocess.s11_load_calibration_bundle_path =
-            optional_string(*preprocess_obj, "s11_load_calibration_bundle_path", "");
-        config.preprocess.s11_reference_bundle_path = optional_string(*preprocess_obj, "s11_reference_bundle_path", "");
+        const auto* s21_obj = as_object(required_field(*preprocess_obj, "s21"), "preprocess.s21");
+        config.preprocess.s21.calibration = parse_preprocess_asset(*s21_obj, "calibration", "preprocess.s21");
+        config.preprocess.s21.reference = parse_preprocess_asset(*s21_obj, "reference", "preprocess.s21");
+
+        const auto* s11_obj = as_object(required_field(*preprocess_obj, "s11"), "preprocess.s11");
+        const auto* s11_calibration_obj =
+            as_object(required_field(*s11_obj, "calibration"), "preprocess.s11.calibration");
+        config.preprocess.s11.calibration.open =
+            parse_preprocess_asset(*s11_calibration_obj, "open", "preprocess.s11.calibration");
+        config.preprocess.s11.calibration.short_standard =
+            parse_preprocess_asset(*s11_calibration_obj, "short", "preprocess.s11.calibration");
+        config.preprocess.s11.calibration.load =
+            parse_preprocess_asset(*s11_calibration_obj, "load", "preprocess.s11.calibration");
+        config.preprocess.s11.reference = parse_preprocess_asset(*s11_obj, "reference", "preprocess.s11");
     }
 
     if (const auto* gpr_value = optional_field(*root_obj, "gpr"); gpr_value != nullptr) {
diff --git a/data_acq_and_processing/preprocessing/data_preprocessor/src/main.cpp b/data_acq_and_processing/preprocessing/data_preprocessor/src/main.cpp
index db4745a..9cc8143 100644
--- a/data_acq_and_processing/preprocessing/data_preprocessor/src/main.cpp
+++ b/data_acq_and_processing/preprocessing/data_preprocessor/src/main.cpp
@@ -65,16 +65,16 @@ int main(int argc, char** argv) {
         radar::preprocessing::CalibrationMaster calibration_master(
             radar::preprocessing::make_s21_through_calibrator()
         );
-        calibration_master.load_s21_calibration_bundle(config.preprocess.s21_calibration_bundle_path);
+        calibration_master.load_s21_calibration_bundle(config.preprocess.s21.calibration.bundle_path);
         calibration_master.load_s11_calibration_bundle(
-            config.preprocess.s11_open_calibration_bundle_path,
-            config.preprocess.s11_short_calibration_bundle_path,
-            config.preprocess.s11_load_calibration_bundle_path
+            config.preprocess.s11.calibration.open.bundle_path,
+            config.preprocess.s11.calibration.short_standard.bundle_path,
+            config.preprocess.s11.calibration.load.bundle_path
         );
 
         radar::preprocessing::ReferenceMaster reference_master;
-        reference_master.load_s21_reference_bundle(config.preprocess.s21_reference_bundle_path);
-        reference_master.load_s11_reference_bundle(config.preprocess.s11_reference_bundle_path);
+        reference_master.load_s21_reference_bundle(config.preprocess.s21.reference.bundle_path);
+        reference_master.load_s11_reference_bundle(config.preprocess.s11.reference.bundle_path);
         reference_master.prepare_calibrated(calibration_master, config.run_combos);
 
         radar::preprocessing::DataPreprocessor preprocessor(
diff --git a/data_acq_and_processing/processing/data_processor/include/processing_live_config.hpp b/data_acq_and_processing/processing/data_processor/include/processing_live_config.hpp
index 935fc26..5024564 100644
--- a/data_acq_and_processing/processing/data_processor/include/processing_live_config.hpp
+++ b/data_acq_and_processing/processing/data_processor/include/processing_live_config.hpp
@@ -23,6 +23,7 @@ struct ProcessingLiveConfig {
     float pass_through_y_min_db = -100.0F;
     float pass_through_y_max_db = 0.0F;
     std::string bscan_axis = "abs";
+    std::string bscan_channel = "s21";
     float bscan_cut_m = 0.824F;
     float bscan_max_depth_m = 1.0F;
     float bscan_gain = 1.0F;
diff --git a/data_acq_and_processing/processing/data_processor/src/processing_live_config.cpp b/data_acq_and_processing/processing/data_processor/src/processing_live_config.cpp
index 3d1989b..589fd43 100644
--- a/data_acq_and_processing/processing/data_processor/src/processing_live_config.cpp
+++ b/data_acq_and_processing/processing/data_processor/src/processing_live_config.cpp
@@ -30,11 +30,11 @@ using Json = nlohmann::json;
     throw std::runtime_error("processing.history_command must be one of: none, remove_last, clear_all");
 }
 
-[[nodiscard]] auto parse_pass_through_channel(const std::string& value) -> std::string {
+[[nodiscard]] auto parse_s_parameter_channel(const std::string& value, const std::string& field_name) -> std::string {
     if (value == "s21" || value == "s11") {
         return value;
     }
-    throw std::runtime_error("processing.pass_through_channel must be one of: s21, s11");
+    throw std::runtime_error(field_name + " must be one of: s21, s11");
 }
 
 [[nodiscard]] auto parse_u64_number(const Json& value, const std::string& field_name) -> std::uint64_t {
@@ -112,7 +112,8 @@ using Json = nlohmann::json;
         if (!found->is_string()) {
             throw std::runtime_error("processing.pass_through_channel must be string");
         }
-        config.pass_through_channel = parse_pass_through_channel(found->get<std::string>());
+        config.pass_through_channel =
+            parse_s_parameter_channel(found->get<std::string>(), "processing.pass_through_channel");
     }
     if (const auto found = root.find("pass_through_fixed_y_enabled"); found != root.end()) {
         if (!found->is_boolean()) {
@@ -138,6 +139,12 @@ using Json = nlohmann::json;
         }
         config.bscan_axis = found->get<std::string>();
     }
+    if (const auto found = root.find("bscan_channel"); found != root.end()) {
+        if (!found->is_string()) {
+            throw std::runtime_error("processing.bscan_channel must be string");
+        }
+        config.bscan_channel = parse_s_parameter_channel(found->get<std::string>(), "processing.bscan_channel");
+    }
     if (const auto found = root.find("bscan_cut_m"); found != root.end()) {
         if (!found->is_number()) {
             throw std::runtime_error("processing.bscan_cut_m must be number");
diff --git a/data_acq_and_processing/processing/processors/src/bscan_processor.cpp b/data_acq_and_processing/processing/processors/src/bscan_processor.cpp
index b78f932..e797977 100644
--- a/data_acq_and_processing/processing/processors/src/bscan_processor.cpp
+++ b/data_acq_and_processing/processing/processors/src/bscan_processor.cpp
@@ -6,6 +6,7 @@
 #include <cstddef>
 #include <cstdint>
 #include <limits>
+#include <span>
 #include <string_view>
 #include <utility>
 #include <vector>
@@ -92,15 +93,28 @@ void fft_inplace(std::vector<std::complex<double>>& values, bool inverse) {
     return std::abs(sample);
 }
 
-[[nodiscard]] auto fallback_profile(const ipc::SweepTraceBlock& trace) -> BScanProfile {
-    const std::size_t point_count = std::min(trace.frequency_hz.size(), trace.s21.size());
+[[nodiscard]] auto selected_trace_samples(
+    const ipc::SweepTraceBlock& trace,
+    const ProcessingLiveConfig& live_config
+) -> std::span<const ipc::Complex32> {
+    if (live_config.bscan_channel == "s11") {
+        return trace.s11;
+    }
+    return trace.s21;
+}
+
+[[nodiscard]] auto fallback_profile(
+    const ipc::SweepTraceBlock& trace,
+    std::span<const ipc::Complex32> selected_samples
+) -> BScanProfile {
+    const std::size_t point_count = std::min(trace.frequency_hz.size(), selected_samples.size());
     BScanProfile fallback{};
     fallback.depth_m.reserve(point_count);
     fallback.response.reserve(point_count);
 
     const float denominator = point_count > 1U ? static_cast<float>(point_count - 1U) : 1.0F;
     for (std::size_t index = 0U; index < point_count; ++index) {
-        const auto& sample = trace.s21[index];
+        const auto& sample = selected_samples[index];
         fallback.depth_m.push_back(static_cast<float>(static_cast<float>(index) / denominator));
         fallback.response.push_back(std::sqrt(sample.re * sample.re + sample.im * sample.im));
     }
@@ -111,9 +125,10 @@ void fft_inplace(std::vector<std::complex<double>>& values, bool inverse) {
     const ipc::SweepTraceBlock& trace,
     const ProcessingLiveConfig& live_config
 ) -> BScanProfile {
-    const std::size_t point_count = std::min(trace.frequency_hz.size(), trace.s21.size());
+    const auto selected_samples = selected_trace_samples(trace, live_config);
+    const std::size_t point_count = std::min(trace.frequency_hz.size(), selected_samples.size());
     if (point_count < 2U) {
-        return fallback_profile(trace);
+        return fallback_profile(trace, selected_samples);
     }
 
     const double configured_start_hz = static_cast<double>(live_config.bscan_start_freq_mhz) * 1'000'000.0;
@@ -122,55 +137,55 @@ void fft_inplace(std::vector<std::complex<double>>& values, bool inverse) {
     const double stop_hz = std::max(configured_start_hz, configured_stop_hz);
 
     std::vector<double> filtered_freq_hz{};
-    std::vector<std::complex<double>> filtered_s21{};
+    std::vector<std::complex<double>> filtered_samples{};
     filtered_freq_hz.reserve(point_count);
-    filtered_s21.reserve(point_count);
+    filtered_samples.reserve(point_count);
 
     for (std::size_t index = 0U; index < point_count; ++index) {
         const double frequency_hz = static_cast<double>(trace.frequency_hz[index]);
         if (frequency_hz < start_hz || frequency_hz > stop_hz) {
             continue;
         }
-        const auto& sample = trace.s21[index];
+        const auto& sample = selected_samples[index];
         filtered_freq_hz.push_back(frequency_hz);
-        filtered_s21.emplace_back(static_cast<double>(sample.re), static_cast<double>(sample.im));
+        filtered_samples.emplace_back(static_cast<double>(sample.re), static_cast<double>(sample.im));
     }
 
     if (filtered_freq_hz.size() < 2U) {
-        return fallback_profile(trace);
+        return fallback_profile(trace, selected_samples);
     }
 
     const std::size_t filtered_count = filtered_freq_hz.size();
     const double df = (filtered_freq_hz.back() - filtered_freq_hz.front()) / static_cast<double>(filtered_count - 1U);
     if (df <= 0.0) {
-        return fallback_profile(trace);
+        return fallback_profile(trace, selected_samples);
     }
 
     const auto start_bin = static_cast<std::int64_t>(std::llround(filtered_freq_hz.front() / df));
     if (start_bin < 0) {
-        return fallback_profile(trace);
+        return fallback_profile(trace, selected_samples);
     }
 
     const auto start_index = static_cast<std::size_t>(start_bin);
     if (start_index > (std::numeric_limits<std::size_t>::max() / 2U)) {
-        return fallback_profile(trace);
+        return fallback_profile(trace, selected_samples);
     }
     if (start_index > (std::numeric_limits<std::size_t>::max() - filtered_count + 1U)) {
-        return fallback_profile(trace);
+        return fallback_profile(trace, selected_samples);
     }
 
     const std::size_t min_fft_len = 2U * (start_index + filtered_count - 1U);
     const std::size_t fft_len = next_power_of_two(min_fft_len);
     if (fft_len < min_fft_len || (fft_len & (fft_len - 1U)) != 0U) {
-        return fallback_profile(trace);
+        return fallback_profile(trace, selected_samples);
     }
     if (start_index > fft_len || filtered_count > (fft_len - start_index)) {
-        return fallback_profile(trace);
+        return fallback_profile(trace, selected_samples);
     }
 
     std::vector<std::complex<double>> spectrum(fft_len, std::complex<double>(0.0, 0.0));
     for (std::size_t index = 0U; index < filtered_count; ++index) {
-        spectrum[start_index + index] = filtered_s21[index];
+        spectrum[start_index + index] = filtered_samples[index];
     }
 
     fft_inplace(spectrum, true);
diff --git a/python_app/gui/app_window.py b/python_app/gui/app_window.py
index af6b1b9..23640d7 100644
--- a/python_app/gui/app_window.py
+++ b/python_app/gui/app_window.py
@@ -24,6 +24,7 @@ from python_app.models.dataset_model import ResultCollection, SweepCollection
 from python_app.models.run_config_model import RunConfigModel
 from python_app.orchestration.config_writer import ConfigWriter
 from python_app.orchestration.live_processing_config import ProcessingLiveConfigWriter
+from python_app.orchestration.preprocess_assets import PREPROCESS_ASSET_KEYS, preprocess_asset_model
 from python_app.orchestration.process_supervisor import ProcessSupervisor
 from python_app.orchestration.shm_reader import ShmRingReader
 from python_app.storage.npz_store import NpzStore
@@ -78,8 +79,10 @@ class AppWindow(
     def _init_preprocess_state(self) -> None:
         """Initialize preprocessing dialog and selected set names."""
         self._preprocess_dialog: PreprocessDialog | None = None
-        self._selected_s21_calibration_set = str(self._defaults_config.preprocess.s21_calibration_set)
-        self._selected_s21_reference_set = str(self._defaults_config.preprocess.s21_reference_set)
+        self._selected_preprocess_sets = {
+            key: str(preprocess_asset_model(self._defaults_config, key).set_name)
+            for key in PREPROCESS_ASSET_KEYS
+        }
 
     def _init_capture_state(self) -> None:
         """Initialize one-shot capture and sequence-control flags."""
diff --git a/python_app/gui/controllers/app_window_config_mixin.py b/python_app/gui/controllers/app_window_config_mixin.py
index 7389e17..989ff48 100644
--- a/python_app/gui/controllers/app_window_config_mixin.py
+++ b/python_app/gui/controllers/app_window_config_mixin.py
@@ -7,6 +7,7 @@ from python_app.models.run_config_model import ComboModel, GprRxGeometryModel, G
 from python_app.models.run_config_validation import validate_gpr_model
 from python_app.orchestration.config_writer import parse_combos_from_text
 from python_app.orchestration.live_processing_config import ProcessingLiveConfig
+from python_app.orchestration.preprocess_assets import PREPROCESS_ASSET_KEYS, preprocess_asset_model
 from python_app.storage.npz_store import radar_key_from_config
 
 
@@ -118,8 +119,10 @@ class AppWindowConfigMixin:
         if self._switches_are_effectively_static(config):
             config.combos = [ComboModel(input=0, output=0)]
 
-        config.preprocess.s21_calibration_set = self._selected_s21_calibration_set
-        config.preprocess.s21_reference_set = self._selected_s21_reference_set
+        for key in PREPROCESS_ASSET_KEYS:
+            asset = preprocess_asset_model(config, key)
+            asset.set_name = self._selected_preprocess_sets[key]
+            asset.bundle_path = ""
         config.gpr.mode = self._gpr_config_mode.currentText()
         config.gpr.relative_permittivity = float(self._gpr_relative_permittivity.value())
         config.gpr.tx_geometry = self._parse_gpr_tx_geometry_text(self._gpr_tx_geometry_input.toPlainText())
@@ -132,7 +135,7 @@ class AppWindowConfigMixin:
         return config
 
     def _radar_key(self, config: RunConfigModel) -> str:
-        """Build radar key used by calibration/reference storage lookup."""
+        """Build radar key used by preprocess-set storage lookup."""
         return radar_key_from_config(
             model_name=config.radar.model,
             serial=config.radar.serial,
@@ -158,6 +161,7 @@ class AppWindowConfigMixin:
             pass_through_y_min_db=min(y_min_db, y_max_db),
             pass_through_y_max_db=max(y_min_db, y_max_db),
             bscan_axis=self._bscan_axis.currentText(),
+            bscan_channel=self._bscan_channel.currentText(),
             bscan_cut_m=float(self._bscan_cut_m.value()),
             bscan_max_depth_m=float(self._bscan_max_depth_m.value()),
             bscan_gain=float(self._bscan_gain.value()),
diff --git a/python_app/gui/controllers/app_window_pipeline_mixin.py b/python_app/gui/controllers/app_window_pipeline_mixin.py
index 9c3550d..5ba26a7 100644
--- a/python_app/gui/controllers/app_window_pipeline_mixin.py
+++ b/python_app/gui/controllers/app_window_pipeline_mixin.py
@@ -9,6 +9,7 @@ from python_app.gui.runtime.history import build_run_history_signature, record_r
 from python_app.hardware_full.librevna_service import LibreVnaService
 from python_app.models.dataset_model import ComboKey, ResultCollection, SweepCollection
 from python_app.models.run_config_model import RunConfigModel
+from python_app.orchestration.preprocess_assets import PREPROCESS_ASSET_KEYS, PREPROCESS_ASSET_SPECS, preprocess_asset_model
 from python_app.orchestration.shm_reader import ShmRingReader
 
 
@@ -38,28 +39,26 @@ class AppWindowPipelineMixin:
             run_signature = self._build_run_history_signature(config)
             radar_key = self._radar_key(config)
 
-            if not config.preprocess.s21_calibration_set or not config.preprocess.s21_reference_set:
-                raise RuntimeError("Select calibration and reference sets in Preprocessing Panel before Start")
+            missing_assets = [
+                PREPROCESS_ASSET_SPECS[key].display_name
+                for key in PREPROCESS_ASSET_KEYS
+                if not preprocess_asset_model(config, key).set_name
+            ]
+            if missing_assets:
+                raise RuntimeError(
+                    "Select all required preprocess sets in Preprocessing Panel before Start: "
+                    + ", ".join(missing_assets)
+                )
 
             combo_keys = [ComboKey(input_pos=combo.input, output_pos=combo.output) for combo in config.combos]
 
-            if not self._store.has_combo_coverage(
-                "calibration", radar_key, config.preprocess.s21_calibration_set, combo_keys
-            ):
-                raise RuntimeError("Selected calibration set does not cover requested run combos")
-            if not self._store.has_combo_coverage(
-                "reference", radar_key, config.preprocess.s21_reference_set, combo_keys
-            ):
-                raise RuntimeError("Selected reference set does not cover requested run combos")
+            for key in PREPROCESS_ASSET_KEYS:
+                spec = PREPROCESS_ASSET_SPECS[key]
+                asset = preprocess_asset_model(config, key)
+                if not self._store.has_combo_coverage(spec.set_kind, radar_key, asset.set_name, combo_keys):
+                    raise RuntimeError(f"Selected {spec.display_name} set does not cover requested run combos")
 
-            calibration_bundle, reference_bundle = self._config_writer.prepare_s21_bundles(
-                self._store,
-                radar_key,
-                config.preprocess.s21_calibration_set,
-                config.preprocess.s21_reference_set,
-            )
-            config.preprocess.s21_calibration_bundle_path = str(calibration_bundle)
-            config.preprocess.s21_reference_bundle_path = str(reference_bundle)
+            self._config_writer.prepare_preprocess_bundles(self._store, radar_key, config)
             config.runtime.continuous = not single_capture
 
             if not single_capture:
diff --git a/python_app/gui/controllers/app_window_plot_mixin.py b/python_app/gui/controllers/app_window_plot_mixin.py
index 0aa0fe8..7d7a421 100644
--- a/python_app/gui/controllers/app_window_plot_mixin.py
+++ b/python_app/gui/controllers/app_window_plot_mixin.py
@@ -389,7 +389,10 @@ class AppWindowPlotMixin:
         self._bscan_plot.addItem(image_item)
         self._bscan_plot.setXRange(x_min, x_max, padding=0.02)
         self._bscan_plot.setYRange(depth_min, depth_max, padding=0.02)
-        self._bscan_plot.setTitle(f"B-scan in{display_key[0]}/out{display_key[1]} | sweeps={sweep_count}")
+        bscan_channel = self._bscan_channel.currentText().upper()
+        self._bscan_plot.setTitle(
+            f"B-scan {bscan_channel} in{display_key[0]}/out{display_key[1]} | sweeps={sweep_count}"
+        )
         return True
 
     def _sync_bscan_history_from_results(self) -> None:
@@ -793,12 +796,13 @@ class AppWindowPlotMixin:
                     return True
         return False
 
-    def _draw_single_trace(self, trace: TraceData, title: str) -> None:
+    def _draw_single_trace(self, trace: TraceData, title: str, *, channel: str = "s21") -> None:
         """Draw one trace on stacked magnitude/phase plots."""
         show_magnitude = self._show_magnitude_curves()
         show_phase = self._show_phase_curves()
         magnitude_plot = self._trace_magnitude_plot
         phase_plot = self._trace_phase_plot
+        samples = trace.s11 if channel == "s11" else trace.s21
 
         magnitude_plot.setVisible(show_magnitude)
         phase_plot.setVisible(show_phase)
@@ -822,7 +826,7 @@ class AppWindowPlotMixin:
             phase_plot.setTitle(title)
 
         if show_magnitude:
-            magnitude_db = 20.0 * np.log10(np.maximum(np.abs(trace.s21), 1e-12))
+            magnitude_db = 20.0 * np.log10(np.maximum(np.abs(samples), 1e-12))
             magnitude_curve = pg.PlotCurveItem(
                 trace.frequency_hz,
                 magnitude_db,
@@ -834,7 +838,7 @@ class AppWindowPlotMixin:
             ] = magnitude_curve
 
         if show_phase:
-            phase_deg = np.degrees(np.angle(trace.s21))
+            phase_deg = np.degrees(np.angle(samples))
             phase_curve = pg.PlotCurveItem(
                 trace.frequency_hz,
                 phase_deg,
diff --git a/python_app/gui/controllers/app_window_preprocess_mixin.py b/python_app/gui/controllers/app_window_preprocess_mixin.py
index 946d074..d3ad35b 100644
--- a/python_app/gui/controllers/app_window_preprocess_mixin.py
+++ b/python_app/gui/controllers/app_window_preprocess_mixin.py
@@ -3,11 +3,17 @@
 from __future__ import annotations
 
 from python_app.gui.preprocess_dialog import PreprocessDialog
+from python_app.orchestration.preprocess_assets import (
+    PREPROCESS_ASSET_KEYS,
+    PREPROCESS_ASSET_SPECS,
+    preprocess_asset_channel,
+    preprocess_asset_display_name,
+)
 from python_app.workflows.sequential_capture_workflow import SequentialCaptureSession
 
 
 class AppWindowPreprocessMixin:
-    """Handles calibration/reference set management and capture workflow."""
+    """Handles preprocess set management and sequential capture workflows."""
 
     def _open_preprocess_panel(self) -> None:
         """Open preprocessing dialog and refresh available sets."""
@@ -38,39 +44,39 @@ class AppWindowPreprocessMixin:
         self._update_capture_dialog_state()
         return dialog
 
-    def _on_preprocess_selection_changed(self, calibration_set: str, reference_set: str) -> None:
+    def _on_preprocess_selection_changed(self) -> None:
         """Persist selected preprocessing set names from dialog."""
-        self._selected_s21_calibration_set = calibration_set.strip()
-        self._selected_s21_reference_set = reference_set.strip()
+        dialog = self._ensure_preprocess_dialog()
+        self._selected_preprocess_sets = dialog.selection_snapshot()
         self._refresh_preprocess_summary_labels()
 
     def _refresh_preprocess_summary_labels(self) -> None:
         """Update compact summary labels in the main window."""
-        self._selected_calibration_label.setText(self._selected_s21_calibration_set or "<not selected>")
-        self._selected_reference_label.setText(self._selected_s21_reference_set or "<not selected>")
+        for key in PREPROCESS_ASSET_KEYS:
+            self._selected_preprocess_labels[key].setText(self._selected_preprocess_sets.get(key, "") or "<not selected>")
 
     def _refresh_sets(self) -> None:
-        """Refresh calibration/reference set lists for current radar key."""
+        """Refresh preprocess set lists for current radar key."""
         config = self._build_config()
         radar_key = self._radar_key(config)
-        calibration_sets = self._store.list_sets("calibration", radar_key)
-        reference_sets = self._store.list_sets("reference", radar_key)
-
         dialog = self._ensure_preprocess_dialog()
-        dialog.set_calibration_sets(calibration_sets)
-        dialog.set_reference_sets(reference_sets)
 
-        if self._selected_s21_calibration_set not in calibration_sets:
-            self._selected_s21_calibration_set = calibration_sets[0] if calibration_sets else ""
-        if self._selected_s21_reference_set not in reference_sets:
-            self._selected_s21_reference_set = reference_sets[0] if reference_sets else ""
+        available_sets = {
+            key: self._store.list_sets(PREPROCESS_ASSET_SPECS[key].set_kind, radar_key)
+            for key in PREPROCESS_ASSET_KEYS
+        }
+        dialog.set_available_sets(available_sets)
 
-        dialog.set_selected_sets(self._selected_s21_calibration_set, self._selected_s21_reference_set)
+        for key, names in available_sets.items():
+            if self._selected_preprocess_sets.get(key, "") not in names:
+                self._selected_preprocess_sets[key] = names[0] if names else ""
+
+        dialog.set_selected_sets(self._selected_preprocess_sets)
         self._refresh_preprocess_summary_labels()
-        self._log(f"Set lists refreshed for key={radar_key}")
+        self._log(f"Preprocess set lists refreshed for key={radar_key}")
 
     def _start_capture_sequence(self, kind: str) -> None:
-        """Start sequential capture session for requested preprocessing kind."""
+        """Start sequential capture session for requested preprocess asset."""
         if self._capture_session is not None:
             self._show_error("Another capture sequence is already active")
             return
@@ -91,18 +97,19 @@ class AppWindowPreprocessMixin:
         try:
             config = self._build_config()
             radar_key = self._radar_key(config)
-            existing_sets = self._store.list_sets(kind, radar_key)
+            existing_sets = self._store.list_sets(PREPROCESS_ASSET_SPECS[kind].set_kind, radar_key)
+            display_name = preprocess_asset_display_name(kind)
             if set_name in existing_sets:
-                raise RuntimeError(f"Set '{set_name}' already exists for {kind} and cannot be overwritten")
+                raise RuntimeError(f"Set '{set_name}' already exists for {display_name} and cannot be overwritten")
 
             session = SequentialCaptureSession(config=config, kind=kind, set_name=set_name)
             session.open()
             self._capture_session = session
 
             dialog.clear_capture_log()
-            dialog.set_status(f"{kind.title()} sequence started")
+            dialog.set_status(f"{display_name} sequence started")
             self._update_capture_dialog_state()
-            self._log(f"{kind.title()} sequence started for set={set_name}; fill all N*M combos")
+            self._log(f"{display_name} sequence started for set={set_name}; fill all N*M combos")
         except Exception as exc:  # noqa: BLE001
             self._cleanup_capture_session()
             self._show_error(f"Failed to start {kind} sequence: {exc}")
@@ -121,9 +128,11 @@ class AppWindowPreprocessMixin:
             trace = session.capture_current_combo()
             state = session.state()
             tx_label, rx_label = dialog.antenna_labels()
+            display_name = preprocess_asset_display_name(session.kind)
+            channel = preprocess_asset_channel(session.kind)
 
             dialog.append_capture_log_entry(
-                kind=session.kind,
+                kind=display_name,
                 captured_count=state.captured_count,
                 total_count=state.total_count,
                 input_pos=trace.combo.input_pos,
@@ -132,11 +141,11 @@ class AppWindowPreprocessMixin:
                 rx_label=rx_label,
             )
 
-            dialog.draw_last_trace(trace, title=f"{session.kind.title()} captured")
-            self._draw_single_trace(trace, title=f"{session.kind.title()} last trace")
+            dialog.draw_last_trace(trace, title=f"{display_name} captured", channel=channel)
+            self._draw_single_trace(trace, title=f"{display_name} last trace", channel=channel)
 
             self._log(
-                f"{session.kind.title()} capture: {state.captured_count}/{state.total_count} | "
+                f"{display_name} capture: {state.captured_count}/{state.total_count} | "
                 f"input={trace.combo.input_pos} output={trace.combo.output_pos}"
             )
 
@@ -144,16 +153,13 @@ class AppWindowPreprocessMixin:
                 radar_key, collection = session.finalize(self._store)
                 set_name = session.set_name
                 kind = session.kind
+                display_name = preprocess_asset_display_name(kind)
                 self._cleanup_capture_session()
 
-                if kind == "calibration":
-                    self._selected_s21_calibration_set = set_name
-                else:
-                    self._selected_s21_reference_set = set_name
-
+                self._selected_preprocess_sets[kind] = set_name
                 self._refresh_sets()
-                dialog.set_status(f"{kind.title()} set saved: {set_name} ({len(collection.traces)} traces)")
-                self._log(f"{kind.title()} sequence completed and saved: set={set_name}, key={radar_key}")
+                dialog.set_status(f"{display_name} set saved: {set_name} ({len(collection.traces)} traces)")
+                self._log(f"{display_name} sequence completed and saved: set={set_name}, key={radar_key}")
                 self._resume_pipeline_if_needed()
             else:
                 self._update_capture_dialog_state()
@@ -166,11 +172,11 @@ class AppWindowPreprocessMixin:
         if self._capture_session is None:
             return
 
-        kind = self._capture_session.kind
+        display_name = preprocess_asset_display_name(self._capture_session.kind)
         self._cleanup_capture_session()
         dialog = self._ensure_preprocess_dialog()
-        dialog.set_status(f"{kind.title()} sequence aborted")
-        self._log(f"{kind.title()} sequence aborted")
+        dialog.set_status(f"{display_name} sequence aborted")
+        self._log(f"{display_name} sequence aborted")
         if resume_pipeline:
             self._resume_pipeline_if_needed()
 
diff --git a/python_app/gui/controllers/sections/preprocess_summary_section.py b/python_app/gui/controllers/sections/preprocess_summary_section.py
index 7f49521..13458d9 100644
--- a/python_app/gui/controllers/sections/preprocess_summary_section.py
+++ b/python_app/gui/controllers/sections/preprocess_summary_section.py
@@ -4,16 +4,18 @@ from __future__ import annotations
 
 from PyQt6.QtWidgets import QFormLayout, QGroupBox, QLabel
 
+from python_app.orchestration.preprocess_assets import PREPROCESS_ASSET_KEYS, preprocess_asset_display_name
+
 
 def build_preprocess_summary_group(owner) -> QGroupBox:
-    """Create selected calibration/reference summary section."""
+    """Create selected preprocess-set summary section."""
     group = QGroupBox("Selected Preprocess Sets")
     form = QFormLayout(group)
     form.setFieldGrowthPolicy(QFormLayout.FieldGrowthPolicy.AllNonFixedFieldsGrow)
 
-    owner._selected_calibration_label = QLabel("<not selected>")
-    owner._selected_reference_label = QLabel("<not selected>")
-
-    form.addRow("Calibration", owner._selected_calibration_label)
-    form.addRow("Reference", owner._selected_reference_label)
+    owner._selected_preprocess_labels = {}
+    for key in PREPROCESS_ASSET_KEYS:
+        label = QLabel("<not selected>")
+        owner._selected_preprocess_labels[key] = label
+        form.addRow(preprocess_asset_display_name(key), label)
     return group
diff --git a/python_app/gui/controllers/sections/processing_section.py b/python_app/gui/controllers/sections/processing_section.py
index 0d0cb63..d8e0650 100644
--- a/python_app/gui/controllers/sections/processing_section.py
+++ b/python_app/gui/controllers/sections/processing_section.py
@@ -110,6 +110,9 @@ def build_processing_group(owner) -> QGroupBox:
     owner._bscan_axis = QComboBox()
     owner._bscan_axis.addItems(["abs", "real", "phase"])
 
+    owner._bscan_channel = QComboBox()
+    owner._bscan_channel.addItems(["s21", "s11"])
+
     owner._bscan_cut_m = QDoubleSpinBox()
     owner._bscan_cut_m.setDecimals(3)
     owner._bscan_cut_m.setRange(0.0, 2.0)
@@ -141,6 +144,7 @@ def build_processing_group(owner) -> QGroupBox:
     owner._bscan_stop_freq_mhz.setValue(8800.0)
 
     bscan_form.addRow("Axis", owner._bscan_axis)
+    bscan_form.addRow("Channel", owner._bscan_channel)
     bscan_form.addRow("Cut m", owner._bscan_cut_m)
     bscan_form.addRow("Max depth m", owner._bscan_max_depth_m)
     bscan_form.addRow("Gain", owner._bscan_gain)
@@ -221,6 +225,7 @@ def build_processing_group(owner) -> QGroupBox:
     form.addRow(owner._processing_mode_pages)
 
     owner._bscan_axis.currentTextChanged.connect(owner._on_processing_live_settings_changed)
+    owner._bscan_channel.currentTextChanged.connect(owner._on_processing_live_settings_changed)
     owner._bscan_cut_m.valueChanged.connect(owner._on_processing_live_settings_changed)
     owner._bscan_max_depth_m.valueChanged.connect(owner._on_processing_live_settings_changed)
     owner._bscan_gain.valueChanged.connect(owner._on_processing_live_settings_changed)
diff --git a/python_app/gui/plotting/bscan_history.py b/python_app/gui/plotting/bscan_history.py
index 2b277f3..ecd31ef 100644
--- a/python_app/gui/plotting/bscan_history.py
+++ b/python_app/gui/plotting/bscan_history.py
@@ -22,15 +22,17 @@ def _result_tail(
         for collection in result_history[-history_limit:]
         if int(collection.collection_id) > int(floor_collection_id)
     ]
-    unique_tail: list[ResultCollection] = []
+    unique_reversed_tail: list[ResultCollection] = []
     seen_keys: set[tuple[int, int]] = set()
-    for collection in filtered:
+    for collection in reversed(filtered):
         key = (int(collection.collection_id), int(collection.monotonic_ns))
         if key in seen_keys:
             continue
         seen_keys.add(key)
-        unique_tail.append(collection)
-    return unique_tail
+        unique_reversed_tail.append(collection)
+
+    unique_reversed_tail.reverse()
+    return unique_reversed_tail
 
 
 def build_bscan_signature(
@@ -47,6 +49,7 @@ def build_bscan_signature(
     )
     return (
         str(live_config.bscan_axis),
+        str(live_config.bscan_channel),
         float(live_config.bscan_cut_m),
         float(live_config.bscan_max_depth_m),
         float(live_config.bscan_gain),
diff --git a/python_app/gui/preprocess_dialog.py b/python_app/gui/preprocess_dialog.py
index 6d68c6b..1c2f9a2 100644
--- a/python_app/gui/preprocess_dialog.py
+++ b/python_app/gui/preprocess_dialog.py
@@ -1,4 +1,4 @@
-"""Dialog for calibration/reference set selection and sequential capture."""
+"""Dialog for preprocess set selection and sequential capture."""
 
 from __future__ import annotations
 
@@ -6,6 +6,7 @@ from PyQt6.QtCore import pyqtSignal
 from PyQt6.QtWidgets import (
     QComboBox,
     QDialog,
+    QFormLayout,
     QGridLayout,
     QGroupBox,
     QHBoxLayout,
@@ -15,23 +16,24 @@ from PyQt6.QtWidgets import (
     QPushButton,
     QVBoxLayout,
 )
-import pyqtgraph as pg
 import numpy as np
+import pyqtgraph as pg
 
 from python_app.models.dataset_model import TraceData
+from python_app.orchestration.preprocess_assets import (
+    PREPROCESS_ASSET_KEYS,
+    PREPROCESS_ASSET_SPECS,
+    S11_PREPROCESS_ASSET_KEYS,
+    S21_PREPROCESS_ASSET_KEYS,
+    preprocess_asset_display_name,
+)
 
 
 class PreprocessDialog(QDialog):
-    """Standalone dialog for preprocessing capture workflows.
-
-    The dialog combines three concerns:
-    1. Set selection (calibration/reference).
-    2. Sequential capture controls for filling all N*M combinations.
-    3. Quick preview of the last captured trace.
-    """
+    """Standalone dialog for preprocess set selection and capture workflows."""
 
     refresh_requested = pyqtSignal()
-    selection_changed = pyqtSignal(str, str)
+    selection_changed = pyqtSignal()
     start_sequence_requested = pyqtSignal(str)
     capture_next_requested = pyqtSignal()
     abort_sequence_requested = pyqtSignal()
@@ -39,13 +41,14 @@ class PreprocessDialog(QDialog):
     def __init__(self, parent=None) -> None:
         """Initialize window metadata and compose dialog UI."""
         super().__init__(parent)
+        self._set_combos: dict[str, QComboBox] = {}
         self._init_window()
         self._build_ui()
 
     def _init_window(self) -> None:
         """Set static window properties."""
         self.setWindowTitle("Preprocessing Setup")
-        self.resize(1040, 760)
+        self.resize(1120, 820)
 
     def _build_ui(self) -> None:
         """Build root dialog layout and all sections."""
@@ -57,28 +60,33 @@ class PreprocessDialog(QDialog):
 
     def _build_sets_group(self) -> QGroupBox:
         """Build set-management controls used for preprocessing snapshots."""
-        group = QGroupBox("Calibration / Reference Sets", self)
-        layout = QGridLayout(group)
+        group = QGroupBox("Preprocess Sets", self)
+        layout = QVBoxLayout(group)
 
+        header_row = QHBoxLayout()
         self._set_name_input = QLineEdit("set_001", group)
-        self._calibration_combo = QComboBox(group)
-        self._reference_combo = QComboBox(group)
-
         refresh_button = QPushButton("Refresh Sets", group)
         refresh_button.clicked.connect(self.refresh_requested.emit)
+        header_row.addWidget(QLabel("Set name"))
+        header_row.addWidget(self._set_name_input, stretch=1)
+        header_row.addWidget(refresh_button)
+        layout.addLayout(header_row)
 
-        self._calibration_combo.currentTextChanged.connect(self._emit_selection_changed)
-        self._reference_combo.currentTextChanged.connect(self._emit_selection_changed)
+        layout.addWidget(self._build_selector_group("S21", S21_PREPROCESS_ASSET_KEYS, group))
+        layout.addWidget(self._build_selector_group("S11", S11_PREPROCESS_ASSET_KEYS, group))
+        return group
 
-        layout.addWidget(QLabel("Set name"), 0, 0)
-        layout.addWidget(self._set_name_input, 0, 1)
-        layout.addWidget(refresh_button, 0, 2)
+    def _build_selector_group(self, title: str, keys: tuple[str, ...], parent: QGroupBox) -> QGroupBox:
+        """Build one selector subgroup for a channel family."""
+        group = QGroupBox(title, parent)
+        form = QFormLayout(group)
+        form.setFieldGrowthPolicy(QFormLayout.FieldGrowthPolicy.AllNonFixedFieldsGrow)
 
-        layout.addWidget(QLabel("Calibration set"), 1, 0)
-        layout.addWidget(self._calibration_combo, 1, 1, 1, 2)
-
-        layout.addWidget(QLabel("Reference set"), 2, 0)
-        layout.addWidget(self._reference_combo, 2, 1, 1, 2)
+        for key in keys:
+            combo = QComboBox(group)
+            combo.currentTextChanged.connect(self._emit_selection_changed)
+            self._set_combos[key] = combo
+            form.addRow(self._asset_row_label(key), combo)
         return group
 
     def _build_sequence_group(self) -> QGroupBox:
@@ -95,8 +103,6 @@ class PreprocessDialog(QDialog):
         self._tx_antenna_label_input.setPlaceholderText("e.g. TX_A")
         self._rx_antenna_label_input.setPlaceholderText("e.g. RX_B")
 
-        button_row = self._build_sequence_button_row(group)
-
         layout.addWidget(QLabel("Active type"), 0, 0)
         layout.addWidget(self._active_kind_label, 0, 1)
         layout.addWidget(QLabel("Progress"), 1, 0)
@@ -107,22 +113,26 @@ class PreprocessDialog(QDialog):
         layout.addWidget(self._tx_antenna_label_input, 3, 1)
         layout.addWidget(QLabel("RX antenna label"), 4, 0)
         layout.addWidget(self._rx_antenna_label_input, 4, 1)
-        layout.addLayout(button_row, 5, 0, 1, 2)
+        layout.addLayout(self._build_sequence_button_grid(group), 5, 0, 1, 2)
+        layout.addLayout(self._build_sequence_action_row(group), 6, 0, 1, 2)
 
         self._capture_log = QPlainTextEdit(group)
         self._capture_log.setReadOnly(True)
         self._capture_log.setPlaceholderText("Capture history per combo")
-        layout.addWidget(self._capture_log, 6, 0, 1, 2)
+        layout.addWidget(self._capture_log, 7, 0, 1, 2)
         return group
 
-    def _build_sequence_button_row(self, parent: QGroupBox) -> QHBoxLayout:
-        """Build action buttons for sequence flow control."""
-        start_calibration_button = QPushButton("Start Calibration Sequence", parent)
-        start_calibration_button.clicked.connect(lambda: self.start_sequence_requested.emit("calibration"))
-
-        start_reference_button = QPushButton("Start Reference Sequence", parent)
-        start_reference_button.clicked.connect(lambda: self.start_sequence_requested.emit("reference"))
+    def _build_sequence_button_grid(self, parent: QGroupBox) -> QGridLayout:
+        """Build per-asset capture start buttons."""
+        layout = QGridLayout()
+        for index, key in enumerate(PREPROCESS_ASSET_KEYS):
+            button = QPushButton(f"Start {preprocess_asset_display_name(key)}", parent)
+            button.clicked.connect(lambda _checked=False, asset_key=key: self.start_sequence_requested.emit(asset_key))
+            layout.addWidget(button, index // 2, index % 2)
+        return layout
 
+    def _build_sequence_action_row(self, parent: QGroupBox) -> QHBoxLayout:
+        """Build capture/abort row for active sequence control."""
         self._capture_next_button = QPushButton("Capture Current Combo", parent)
         self._capture_next_button.clicked.connect(self.capture_next_requested.emit)
         self._capture_next_button.setEnabled(False)
@@ -131,12 +141,11 @@ class PreprocessDialog(QDialog):
         self._abort_button.clicked.connect(self.abort_sequence_requested.emit)
         self._abort_button.setEnabled(False)
 
-        button_row = QHBoxLayout()
-        button_row.addWidget(start_calibration_button)
-        button_row.addWidget(start_reference_button)
-        button_row.addWidget(self._capture_next_button)
-        button_row.addWidget(self._abort_button)
-        return button_row
+        layout = QHBoxLayout()
+        layout.addWidget(self._capture_next_button)
+        layout.addWidget(self._abort_button)
+        layout.addStretch(1)
+        return layout
 
     def _build_status_line(self, root_layout: QVBoxLayout) -> None:
         """Build one-line status output for dialog operations."""
@@ -155,13 +164,9 @@ class PreprocessDialog(QDialog):
         """Return requested target set name."""
         return self._set_name_input.text().strip()
 
-    def calibration_set(self) -> str:
-        """Return currently selected calibration set."""
-        return self._calibration_combo.currentText().strip()
-
-    def reference_set(self) -> str:
-        """Return currently selected reference set."""
-        return self._reference_combo.currentText().strip()
+    def selection_snapshot(self) -> dict[str, str]:
+        """Return currently selected set names keyed by preprocess asset key."""
+        return {key: self._set_combos[key].currentText().strip() for key in PREPROCESS_ASSET_KEYS}
 
     def antenna_labels(self) -> tuple[str, str]:
         """Return optional TX/RX user labels used in capture logs."""
@@ -209,7 +214,8 @@ class PreprocessDialog(QDialog):
             self._abort_button.setEnabled(False)
             return
 
-        self._active_kind_label.setText(kind)
+        active_label = preprocess_asset_display_name(kind) if kind in PREPROCESS_ASSET_SPECS else kind
+        self._active_kind_label.setText(active_label)
         self._progress_label.setText(f"{captured_count} / {total_count}")
         if next_input is None or next_output is None:
             self._combo_label.setText("<complete>")
@@ -220,35 +226,32 @@ class PreprocessDialog(QDialog):
             self._capture_next_button.setEnabled(True)
             self._abort_button.setEnabled(True)
 
-    def set_calibration_sets(self, names: list[str]) -> None:
-        """Replace calibration set choices while preserving current selection when possible."""
-        self._set_combo_items(self._calibration_combo, names, self.calibration_set())
+    def set_available_sets(self, available_sets: dict[str, list[str]]) -> None:
+        """Replace combo-box choices for all preprocess assets."""
+        for key in PREPROCESS_ASSET_KEYS:
+            combo = self._set_combos[key]
+            self._set_combo_items(combo, available_sets.get(key, []), combo.currentText().strip())
 
-    def set_reference_sets(self, names: list[str]) -> None:
-        """Replace reference set choices while preserving current selection when possible."""
-        self._set_combo_items(self._reference_combo, names, self.reference_set())
-
-    def set_selected_sets(self, calibration_set: str, reference_set: str) -> None:
-        """Apply selected set names to both comboboxes and emit selection update."""
-        if calibration_set:
-            index = self._calibration_combo.findText(calibration_set)
+    def set_selected_sets(self, selected_sets: dict[str, str]) -> None:
+        """Apply selected set names to all comboboxes and emit selection update."""
+        for key in PREPROCESS_ASSET_KEYS:
+            selected_value = selected_sets.get(key, "")
+            if not selected_value:
+                continue
+            combo = self._set_combos[key]
+            index = combo.findText(selected_value)
             if index >= 0:
-                self._calibration_combo.setCurrentIndex(index)
-
-        if reference_set:
-            index = self._reference_combo.findText(reference_set)
-            if index >= 0:
-                self._reference_combo.setCurrentIndex(index)
-
+                combo.setCurrentIndex(index)
         self._emit_selection_changed()
 
     def set_status(self, message: str) -> None:
         """Set short human-readable status line."""
         self._status_label.setText(message)
 
-    def draw_last_trace(self, trace: TraceData, title: str) -> None:
-        """Draw the latest captured sweep trace in dB scale."""
-        magnitude_db = 20.0 * np.log10(np.maximum(np.abs(trace.s21), 1e-12))
+    def draw_last_trace(self, trace: TraceData, title: str, *, channel: str) -> None:
+        """Draw the latest captured sweep trace for the requested channel in dB scale."""
+        samples = trace.s11 if channel == "s11" else trace.s21
+        magnitude_db = 20.0 * np.log10(np.maximum(np.abs(samples), 1e-12))
         self._preview_plot.clear()
         self._preview_plot.plot(
             trace.frequency_hz,
@@ -261,8 +264,13 @@ class PreprocessDialog(QDialog):
         )
 
     def _emit_selection_changed(self) -> None:
-        """Emit current calibration/reference selection."""
-        self.selection_changed.emit(self.calibration_set(), self.reference_set())
+        """Emit current selection snapshot change."""
+        self.selection_changed.emit()
+
+    @staticmethod
+    def _asset_row_label(key: str) -> str:
+        """Return short selector label for one preprocess asset."""
+        return preprocess_asset_display_name(key)
 
     @staticmethod
     def _set_combo_items(combo: QComboBox, names: list[str], current_text: str) -> None:
diff --git a/python_app/gui/runtime/history.py b/python_app/gui/runtime/history.py
index 1d7c25e..9441fe1 100644
--- a/python_app/gui/runtime/history.py
+++ b/python_app/gui/runtime/history.py
@@ -7,6 +7,7 @@ from typing import TypeVar
 
 from python_app.models.dataset_model import ResultCollection, SweepCollection
 from python_app.models.run_config_model import RunConfigModel
+from python_app.orchestration.preprocess_assets import PREPROCESS_ASSET_KEYS, preprocess_asset_model
 
 THistoryCollection = TypeVar("THistoryCollection", SweepCollection, ResultCollection)
 
@@ -63,6 +64,7 @@ def build_run_history_signature(
 ) -> tuple[object, ...]:
     """Build deterministic signature to detect run-settings changes (excluding live processing params)."""
     combos_signature = tuple((int(combo.input), int(combo.output)) for combo in config.combos)
+    preprocess_signature = tuple(preprocess_asset_model(config, key).set_name for key in PREPROCESS_ASSET_KEYS)
     return (
         str(config.radar.driver_mode),
         str(config.radar.serial),
@@ -79,8 +81,7 @@ def build_run_history_signature(
         str(config.output_switch.driver),
         int(config.output_switch.positions),
         bool(config.output_switch.invert_logic),
-        str(config.preprocess.s21_calibration_set),
-        str(config.preprocess.s21_reference_set),
+        preprocess_signature,
         combos_signature,
     )
 
diff --git a/python_app/hardware_full/librevna_backends.py b/python_app/hardware_full/librevna_backends.py
index 3bfd97c..61d66bb 100644
--- a/python_app/hardware_full/librevna_backends.py
+++ b/python_app/hardware_full/librevna_backends.py
@@ -8,6 +8,7 @@ from typing import Any, Protocol
 
 import numpy as np
 
+from python_app.hardware_full.librevna_driver.models import SweepResult
 from python_app.models.run_config_model import RadarSweepModel
 
 
@@ -30,8 +31,8 @@ class LibreVnaBackend(Protocol):
     def read_device_limits(self) -> dict[str, float | int]:
         """Query runtime device limits."""
 
-    def acquire_s21(self) -> tuple[np.ndarray, np.ndarray]:
-        """Acquire one S21 trace."""
+    def acquire(self) -> SweepResult:
+        """Acquire one sweep with all available traces."""
 
 
 @dataclass(slots=True)
@@ -108,15 +109,21 @@ class NativeLibreVnaBackend:
             "max_power_dbm": float(limits.max_power_dbm),
         }
 
-    def acquire_s21(self) -> tuple[np.ndarray, np.ndarray]:
-        """Acquire one S21 sweep from hardware."""
+    def acquire(self) -> SweepResult:
+        """Acquire one sweep from hardware."""
         if self._settings is None:
             raise RuntimeError("Radar service is not configured")
         if self._device is None:
             raise RuntimeError("Device not found")
 
         result = self._device.vna.acquire(expected_points=self._settings.points, timeout_s=20.0)
-        return np.asarray(result.x, dtype=np.float32), np.asarray(result.trace("s21"), dtype=np.complex64)
+        return SweepResult(
+            x=np.asarray(result.x, dtype=np.float32),
+            traces={
+                "s11": np.asarray(result.trace("s11"), dtype=np.complex64),
+                "s21": np.asarray(result.trace("s21"), dtype=np.complex64),
+            },
+        )
 
 
 @dataclass(slots=True)
@@ -149,15 +156,26 @@ class MockLibreVnaBackend:
         """Mock backend does not support native device limits queries."""
         raise RuntimeError("LibreVNA Python driver is not available")
 
-    def acquire_s21(self) -> tuple[np.ndarray, np.ndarray]:
-        """Generate synthetic S21 values using deterministic phase envelope."""
+    def acquire(self) -> SweepResult:
+        """Generate synthetic S11 and S21 values using deterministic envelopes."""
         if self._settings is None:
             raise RuntimeError("Radar service is not configured")
 
         points = self._settings.points
         freq = np.linspace(self._settings.start_hz, self._settings.stop_hz, points, dtype=np.float32)
         phase = (2.0 * math.pi * np.linspace(0.0, 1.0, points, dtype=np.float32)) + self._mock_phase
-        envelope = 0.6 + 0.4 * np.sin(phase * 0.5)
-        s21 = (envelope * np.cos(phase) + 1j * envelope * np.sin(phase)).astype(np.complex64)
+        s21_envelope = 0.6 + 0.4 * np.sin(phase * 0.5)
+        s11_envelope = 0.25 + 0.15 * np.cos(phase * 0.75)
+        s21 = (s21_envelope * np.cos(phase) + 1j * s21_envelope * np.sin(phase)).astype(np.complex64)
+        reflected_phase = phase * 0.6 + 0.8
+        s11 = (
+            s11_envelope * np.cos(reflected_phase) + 1j * s11_envelope * np.sin(reflected_phase)
+        ).astype(np.complex64)
         self._mock_phase += 0.05
-        return freq, s21
+        return SweepResult(
+            x=freq,
+            traces={
+                "s11": s11,
+                "s21": s21,
+            },
+        )
diff --git a/python_app/hardware_full/librevna_service.py b/python_app/hardware_full/librevna_service.py
index f0c584d..1bb7dd8 100644
--- a/python_app/hardware_full/librevna_service.py
+++ b/python_app/hardware_full/librevna_service.py
@@ -4,9 +4,8 @@ from __future__ import annotations
 
 from dataclasses import dataclass, field
 
-import numpy as np
-
 from python_app.hardware_full.librevna_backends import LibreVnaBackend, MockLibreVnaBackend, NativeLibreVnaBackend
+from python_app.hardware_full.librevna_driver.models import SweepResult
 from python_app.models.run_config_model import RadarSweepModel
 
 
@@ -89,10 +88,10 @@ class LibreVnaService:
             if opened_here:
                 self.close()
 
-    def acquire_s21(self) -> tuple[np.ndarray, np.ndarray]:
-        """Acquire one S21 trace from currently selected backend."""
+    def acquire(self) -> SweepResult:
+        """Acquire one sweep with all available traces from active backend."""
         if self._backend is None:
             raise RuntimeError("LibreVNA backend is not initialized")
         if self._using_mock_backend and not self._driver_available and self.backend_mode != "mock":
             raise RuntimeError("Device not found")
-        return self._backend.acquire_s21()
+        return self._backend.acquire()
diff --git a/python_app/models/dataset_model.py b/python_app/models/dataset_model.py
index 3e7fe24..78ab8ae 100644
--- a/python_app/models/dataset_model.py
+++ b/python_app/models/dataset_model.py
@@ -32,10 +32,11 @@ class ComboKey:
 
 @dataclass(slots=True)
 class TraceData:
-    """One frequency-domain S21 trace for a specific switch combination."""
+    """One frequency-domain trace set for a specific switch combination."""
 
     combo: ComboKey
     frequency_hz: np.ndarray
+    s11: np.ndarray
     s21: np.ndarray
 
 
diff --git a/python_app/models/run_config_codec.py b/python_app/models/run_config_codec.py
index 4d32564..c7b8aed 100644
--- a/python_app/models/run_config_codec.py
+++ b/python_app/models/run_config_codec.py
@@ -8,6 +8,7 @@ from python_app.models.run_config_schema import (
     ComboModel,
     GprRxGeometryModel,
     GprTxGeometryModel,
+    PreprocessAssetModel,
     RunConfigModel,
 )
 from python_app.models.run_config_validation import load_ring_payload, load_switch_payload, validate_gpr_model
@@ -22,6 +23,12 @@ def _as_dict(value: Any, context: str) -> dict[str, Any]:
     return value
 
 
+def _load_preprocess_asset(payload: dict[str, Any], target: PreprocessAssetModel) -> None:
+    """Load preprocess asset fields into target model."""
+    target.set_name = str(payload.get("set_name", target.set_name))
+    target.bundle_path = str(payload.get("bundle_path", target.bundle_path))
+
+
 def run_config_from_dict(payload: dict[str, Any]) -> RunConfigModel:
     """Decode JSON-like payload into :class:`RunConfigModel`."""
     # Schema carries only minimal-safe fallbacks; operational defaults live in run_config.json.
@@ -65,47 +72,33 @@ def run_config_from_dict(payload: dict[str, Any]) -> RunConfigModel:
         run_payload.get("processing_live_config_path", model.runtime.processing_live_config_path)
     )
 
-    model.preprocess.s21_calibration_set = str(
-        preprocess_payload.get("s21_calibration_set", model.preprocess.s21_calibration_set)
+    s21_preprocess_payload = _as_dict(preprocess_payload.get("s21"), "preprocess.s21")
+    _load_preprocess_asset(
+        _as_dict(s21_preprocess_payload.get("calibration"), "preprocess.s21.calibration"),
+        model.preprocess.s21.calibration,
     )
-    model.preprocess.s21_reference_set = str(
-        preprocess_payload.get("s21_reference_set", model.preprocess.s21_reference_set)
+    _load_preprocess_asset(
+        _as_dict(s21_preprocess_payload.get("reference"), "preprocess.s21.reference"),
+        model.preprocess.s21.reference,
     )
-    model.preprocess.s21_calibration_bundle_path = str(
-        preprocess_payload.get(
-            "s21_calibration_bundle_path",
-            model.preprocess.s21_calibration_bundle_path,
-        )
+
+    s11_preprocess_payload = _as_dict(preprocess_payload.get("s11"), "preprocess.s11")
+    s11_calibration_payload = _as_dict(s11_preprocess_payload.get("calibration"), "preprocess.s11.calibration")
+    _load_preprocess_asset(
+        _as_dict(s11_calibration_payload.get("open"), "preprocess.s11.calibration.open"),
+        model.preprocess.s11.calibration.open,
     )
-    model.preprocess.s21_reference_bundle_path = str(
-        preprocess_payload.get(
-            "s21_reference_bundle_path",
-            model.preprocess.s21_reference_bundle_path,
-        )
+    _load_preprocess_asset(
+        _as_dict(s11_calibration_payload.get("short"), "preprocess.s11.calibration.short"),
+        model.preprocess.s11.calibration.short,
     )
-    model.preprocess.s11_open_calibration_bundle_path = str(
-        preprocess_payload.get(
-            "s11_open_calibration_bundle_path",
-            model.preprocess.s11_open_calibration_bundle_path,
-        )
+    _load_preprocess_asset(
+        _as_dict(s11_calibration_payload.get("load"), "preprocess.s11.calibration.load"),
+        model.preprocess.s11.calibration.load,
     )
-    model.preprocess.s11_short_calibration_bundle_path = str(
-        preprocess_payload.get(
-            "s11_short_calibration_bundle_path",
-            model.preprocess.s11_short_calibration_bundle_path,
-        )
-    )
-    model.preprocess.s11_load_calibration_bundle_path = str(
-        preprocess_payload.get(
-            "s11_load_calibration_bundle_path",
-            model.preprocess.s11_load_calibration_bundle_path,
-        )
-    )
-    model.preprocess.s11_reference_bundle_path = str(
-        preprocess_payload.get(
-            "s11_reference_bundle_path",
-            model.preprocess.s11_reference_bundle_path,
-        )
+    _load_preprocess_asset(
+        _as_dict(s11_preprocess_payload.get("reference"), "preprocess.s11.reference"),
+        model.preprocess.s11.reference,
     )
 
     model.gpr.mode = str(gpr_payload.get("mode", model.gpr.mode))
@@ -213,14 +206,36 @@ def run_config_to_dict(model: RunConfigModel) -> dict[str, Any]:
             "combos": [{"input": combo.input, "output": combo.output} for combo in model.combos],
         },
         "preprocess": {
-            "s21_calibration_set": model.preprocess.s21_calibration_set,
-            "s21_reference_set": model.preprocess.s21_reference_set,
-            "s21_calibration_bundle_path": model.preprocess.s21_calibration_bundle_path,
-            "s21_reference_bundle_path": model.preprocess.s21_reference_bundle_path,
-            "s11_open_calibration_bundle_path": model.preprocess.s11_open_calibration_bundle_path,
-            "s11_short_calibration_bundle_path": model.preprocess.s11_short_calibration_bundle_path,
-            "s11_load_calibration_bundle_path": model.preprocess.s11_load_calibration_bundle_path,
-            "s11_reference_bundle_path": model.preprocess.s11_reference_bundle_path,
+            "s21": {
+                "calibration": {
+                    "set_name": model.preprocess.s21.calibration.set_name,
+                    "bundle_path": model.preprocess.s21.calibration.bundle_path,
+                },
+                "reference": {
+                    "set_name": model.preprocess.s21.reference.set_name,
+                    "bundle_path": model.preprocess.s21.reference.bundle_path,
+                },
+            },
+            "s11": {
+                "calibration": {
+                    "open": {
+                        "set_name": model.preprocess.s11.calibration.open.set_name,
+                        "bundle_path": model.preprocess.s11.calibration.open.bundle_path,
+                    },
+                    "short": {
+                        "set_name": model.preprocess.s11.calibration.short.set_name,
+                        "bundle_path": model.preprocess.s11.calibration.short.bundle_path,
+                    },
+                    "load": {
+                        "set_name": model.preprocess.s11.calibration.load.set_name,
+                        "bundle_path": model.preprocess.s11.calibration.load.bundle_path,
+                    },
+                },
+                "reference": {
+                    "set_name": model.preprocess.s11.reference.set_name,
+                    "bundle_path": model.preprocess.s11.reference.bundle_path,
+                },
+            },
         },
         "gpr": {
             "mode": model.gpr.mode,
diff --git a/python_app/models/run_config_model.py b/python_app/models/run_config_model.py
index ecf8686..cb92aba 100644
--- a/python_app/models/run_config_model.py
+++ b/python_app/models/run_config_model.py
@@ -6,6 +6,7 @@ from python_app.models.run_config_schema import (
     GprModel,
     GprRxGeometryModel,
     GprTxGeometryModel,
+    PreprocessAssetModel,
     PreprocessModel,
     RadarModel,
     RadarSweepModel,
@@ -13,6 +14,9 @@ from python_app.models.run_config_schema import (
     RingsModel,
     RunConfigModel,
     RuntimeModel,
+    S11CalibrationModel,
+    S11PreprocessModel,
+    S21PreprocessModel,
     SwitchModel,
 )
 from python_app.models.run_config_validation import (
@@ -26,6 +30,7 @@ __all__ = [
     "GprModel",
     "GprRxGeometryModel",
     "GprTxGeometryModel",
+    "PreprocessAssetModel",
     "PreprocessModel",
     "RadarModel",
     "RadarSweepModel",
@@ -33,6 +38,9 @@ __all__ = [
     "RingsModel",
     "RunConfigModel",
     "RuntimeModel",
+    "S11CalibrationModel",
+    "S11PreprocessModel",
+    "S21PreprocessModel",
     "SwitchModel",
     "load_ring_payload",
     "load_switch_payload",
diff --git a/python_app/models/run_config_schema.py b/python_app/models/run_config_schema.py
index 89bb5ef..f209267 100644
--- a/python_app/models/run_config_schema.py
+++ b/python_app/models/run_config_schema.py
@@ -85,18 +85,45 @@ class RuntimeModel:
     processing_live_config_path: str = ""
 
 
+@dataclass(slots=True)
+class PreprocessAssetModel:
+    """One preprocessing asset selected for live acquisition."""
+
+    set_name: str = ""
+    bundle_path: str = ""
+
+
+@dataclass(slots=True)
+class S21PreprocessModel:
+    """Two-port S21 preprocessing assets."""
+
+    calibration: PreprocessAssetModel = field(default_factory=PreprocessAssetModel)
+    reference: PreprocessAssetModel = field(default_factory=PreprocessAssetModel)
+
+
+@dataclass(slots=True)
+class S11CalibrationModel:
+    """One-port S11 OSL calibration assets."""
+
+    open: PreprocessAssetModel = field(default_factory=PreprocessAssetModel)
+    short: PreprocessAssetModel = field(default_factory=PreprocessAssetModel)
+    load: PreprocessAssetModel = field(default_factory=PreprocessAssetModel)
+
+
+@dataclass(slots=True)
+class S11PreprocessModel:
+    """One-port S11 preprocessing assets."""
+
+    calibration: S11CalibrationModel = field(default_factory=S11CalibrationModel)
+    reference: PreprocessAssetModel = field(default_factory=PreprocessAssetModel)
+
+
 @dataclass(slots=True)
 class PreprocessModel:
     """Selected preprocessing artifacts for live acquisition."""
 
-    s21_calibration_set: str = ""
-    s21_reference_set: str = ""
-    s21_calibration_bundle_path: str = ""
-    s21_reference_bundle_path: str = ""
-    s11_open_calibration_bundle_path: str = ""
-    s11_short_calibration_bundle_path: str = ""
-    s11_load_calibration_bundle_path: str = ""
-    s11_reference_bundle_path: str = ""
+    s21: S21PreprocessModel = field(default_factory=S21PreprocessModel)
+    s11: S11PreprocessModel = field(default_factory=S11PreprocessModel)
 
 
 @dataclass(slots=True)
diff --git a/python_app/orchestration/config_writer.py b/python_app/orchestration/config_writer.py
index f356c93..242b929 100644
--- a/python_app/orchestration/config_writer.py
+++ b/python_app/orchestration/config_writer.py
@@ -6,6 +6,7 @@ import json
 from pathlib import Path
 
 from python_app.models.run_config_model import RunConfigModel, parse_combos_from_text
+from python_app.orchestration.preprocess_assets import PREPROCESS_ASSET_KEYS, PREPROCESS_ASSET_SPECS, preprocess_asset_model
 from python_app.storage.npz_store import NpzStore
 
 
@@ -17,20 +18,19 @@ class ConfigWriter:
         self._runtime_dir = runtime_dir
         self._runtime_dir.mkdir(parents=True, exist_ok=True)
 
-    def prepare_s21_bundles(
+    def prepare_preprocess_bundles(
         self,
         store: NpzStore,
         radar_key: str,
-        s21_calibration_set: str,
-        s21_reference_set: str,
-    ) -> tuple[Path, Path]:
-        """Export calibration/reference sets into binary bundles for preprocessor."""
-        calibration_bundle = self._runtime_dir / "s21_calibration_bundle.bin"
-        reference_bundle = self._runtime_dir / "s21_reference_bundle.bin"
-
-        store.export_set_bundle("calibration", radar_key, s21_calibration_set, calibration_bundle)
-        store.export_set_bundle("reference", radar_key, s21_reference_set, reference_bundle)
-        return calibration_bundle, reference_bundle
+        config: RunConfigModel,
+    ) -> None:
+        """Export selected preprocess sets into runtime bundles and update config paths."""
+        for key in PREPROCESS_ASSET_KEYS:
+            spec = PREPROCESS_ASSET_SPECS[key]
+            asset = preprocess_asset_model(config, key)
+            bundle_path = self._runtime_dir / spec.runtime_filename
+            store.export_set_bundle(spec.set_kind, radar_key, asset.set_name, bundle_path)
+            asset.bundle_path = str(bundle_path)
 
     def write(self, config: RunConfigModel, output_path: Path) -> Path:
         """Write run configuration JSON file."""
diff --git a/python_app/orchestration/live_processing_config.py b/python_app/orchestration/live_processing_config.py
index 2ae98c2..0902368 100644
--- a/python_app/orchestration/live_processing_config.py
+++ b/python_app/orchestration/live_processing_config.py
@@ -19,6 +19,7 @@ class ProcessingLiveConfig:
     pass_through_y_min_db: float = -100.0
     pass_through_y_max_db: float = 0.0
     bscan_axis: str = "abs"
+    bscan_channel: str = "s21"
     bscan_cut_m: float = 0.824
     bscan_max_depth_m: float = 1.0
     bscan_gain: float = 1.0
@@ -58,6 +59,7 @@ class ProcessingLiveConfig:
             "pass_through_y_min_db": float(self.pass_through_y_min_db),
             "pass_through_y_max_db": float(self.pass_through_y_max_db),
             "bscan_axis": str(self.bscan_axis),
+            "bscan_channel": str(self.bscan_channel),
             "bscan_cut_m": float(self.bscan_cut_m),
             "bscan_max_depth_m": float(self.bscan_max_depth_m),
             "bscan_gain": float(self.bscan_gain),
diff --git a/python_app/orchestration/preprocess_assets.py b/python_app/orchestration/preprocess_assets.py
new file mode 100644
index 0000000..b0d3727
--- /dev/null
+++ b/python_app/orchestration/preprocess_assets.py
@@ -0,0 +1,95 @@
+"""Canonical preprocess asset definitions shared by GUI and runtime orchestration."""
+
+from __future__ import annotations
+
+from dataclasses import dataclass
+
+from python_app.models.run_config_model import PreprocessAssetModel, RunConfigModel
+
+
+@dataclass(frozen=True, slots=True)
+class PreprocessAssetSpec:
+    """Stable description of one preprocess asset."""
+
+    key: str
+    display_name: str
+    set_kind: str
+    runtime_filename: str
+    channel: str
+
+
+PREPROCESS_ASSET_SPECS = {
+    "s21_calibration": PreprocessAssetSpec(
+        key="s21_calibration",
+        display_name="S21 Calibration",
+        set_kind="s21_calibration",
+        runtime_filename="s21_calibration_bundle.bin",
+        channel="s21",
+    ),
+    "s21_reference": PreprocessAssetSpec(
+        key="s21_reference",
+        display_name="S21 Reference",
+        set_kind="s21_reference",
+        runtime_filename="s21_reference_bundle.bin",
+        channel="s21",
+    ),
+    "s11_open": PreprocessAssetSpec(
+        key="s11_open",
+        display_name="S11 Open",
+        set_kind="s11_open",
+        runtime_filename="s11_open_calibration_bundle.bin",
+        channel="s11",
+    ),
+    "s11_short": PreprocessAssetSpec(
+        key="s11_short",
+        display_name="S11 Short",
+        set_kind="s11_short",
+        runtime_filename="s11_short_calibration_bundle.bin",
+        channel="s11",
+    ),
+    "s11_load": PreprocessAssetSpec(
+        key="s11_load",
+        display_name="S11 Load",
+        set_kind="s11_load",
+        runtime_filename="s11_load_calibration_bundle.bin",
+        channel="s11",
+    ),
+    "s11_reference": PreprocessAssetSpec(
+        key="s11_reference",
+        display_name="S11 Reference",
+        set_kind="s11_reference",
+        runtime_filename="s11_reference_bundle.bin",
+        channel="s11",
+    ),
+}
+
+PREPROCESS_ASSET_KEYS = tuple(PREPROCESS_ASSET_SPECS.keys())
+S21_PREPROCESS_ASSET_KEYS = ("s21_calibration", "s21_reference")
+S11_PREPROCESS_ASSET_KEYS = ("s11_open", "s11_short", "s11_load", "s11_reference")
+
+
+def preprocess_asset_model(config: RunConfigModel, key: str) -> PreprocessAssetModel:
+    """Return nested preprocess asset model by canonical asset key."""
+    if key == "s21_calibration":
+        return config.preprocess.s21.calibration
+    if key == "s21_reference":
+        return config.preprocess.s21.reference
+    if key == "s11_open":
+        return config.preprocess.s11.calibration.open
+    if key == "s11_short":
+        return config.preprocess.s11.calibration.short
+    if key == "s11_load":
+        return config.preprocess.s11.calibration.load
+    if key == "s11_reference":
+        return config.preprocess.s11.reference
+    raise KeyError(f"Unknown preprocess asset key: {key}")
+
+
+def preprocess_asset_display_name(key: str) -> str:
+    """Return human-readable label for preprocess asset."""
+    return PREPROCESS_ASSET_SPECS[key].display_name
+
+
+def preprocess_asset_channel(key: str) -> str:
+    """Return associated trace channel for preprocess asset."""
+    return PREPROCESS_ASSET_SPECS[key].channel
diff --git a/python_app/orchestration/shm/decoder.py b/python_app/orchestration/shm/decoder.py
index a6935be..147fa84 100644
--- a/python_app/orchestration/shm/decoder.py
+++ b/python_app/orchestration/shm/decoder.py
@@ -40,16 +40,16 @@ def decode_trace_collection(payload: bytes, expected_magic: int) -> SweepCollect
         freq = np.frombuffer(cursor.read_bytes(freq_bytes), dtype="<f4").astype(np.float32, copy=False)
 
         interleaved_bytes = point_count * 8
-        # Runtime trace payloads now carry S11 before S21. The Python layer
-        # still works with S21 only for now, so consume and discard S11 here.
-        cursor.read_bytes(interleaved_bytes)
-        interleaved = np.frombuffer(cursor.read_bytes(interleaved_bytes), dtype="<f4")
-        s21 = (interleaved[0::2] + 1j * interleaved[1::2]).astype(np.complex64, copy=False)
+        s11_interleaved = np.frombuffer(cursor.read_bytes(interleaved_bytes), dtype="<f4")
+        s21_interleaved = np.frombuffer(cursor.read_bytes(interleaved_bytes), dtype="<f4")
+        s11 = (s11_interleaved[0::2] + 1j * s11_interleaved[1::2]).astype(np.complex64, copy=False)
+        s21 = (s21_interleaved[0::2] + 1j * s21_interleaved[1::2]).astype(np.complex64, copy=False)
 
         traces.append(
             TraceData(
                 combo=ComboKey(input_pos=input_pos, output_pos=output_pos),
                 frequency_hz=freq,
+                s11=s11,
                 s21=s21,
             )
         )
diff --git a/python_app/runtime/run_config_smoke.json b/python_app/runtime/run_config_smoke.json
index 16410ba..b7d3116 100644
--- a/python_app/runtime/run_config_smoke.json
+++ b/python_app/runtime/run_config_smoke.json
@@ -60,6 +60,38 @@
         "input": 3,
         "output": 0
       },
+      {
+        "input": 0,
+        "output": 1
+      },
+      {
+        "input": 1,
+        "output": 1
+      },
+      {
+        "input": 2,
+        "output": 1
+      },
+      {
+        "input": 3,
+        "output": 1
+      },
+      {
+        "input": 0,
+        "output": 2
+      },
+      {
+        "input": 1,
+        "output": 2
+      },
+      {
+        "input": 2,
+        "output": 2
+      },
+      {
+        "input": 3,
+        "output": 2
+      },
       {
         "input": 0,
         "output": 3
@@ -79,14 +111,36 @@
     ]
   },
   "preprocess": {
-    "s21_calibration_set": "smoke_cal",
-    "s21_reference_set": "smoke_ref",
-    "s21_calibration_bundle_path": "/home/europa/Documents/radar_system/python_app/runtime/s21_calibration_bundle.bin",
-    "s21_reference_bundle_path": "/home/europa/Documents/radar_system/python_app/runtime/s21_reference_bundle.bin",
-    "s11_open_calibration_bundle_path": "/home/europa/Documents/radar_system/data_acq_and_processing/preprocessing/testdata/s11_open_calibration_bundle.bin",
-    "s11_short_calibration_bundle_path": "/home/europa/Documents/radar_system/data_acq_and_processing/preprocessing/testdata/s11_short_calibration_bundle.bin",
-    "s11_load_calibration_bundle_path": "/home/europa/Documents/radar_system/data_acq_and_processing/preprocessing/testdata/s11_load_calibration_bundle.bin",
-    "s11_reference_bundle_path": "/home/europa/Documents/radar_system/data_acq_and_processing/preprocessing/testdata/s11_reference_bundle.bin"
+    "s21": {
+      "calibration": {
+        "set_name": "smoke_cal",
+        "bundle_path": "/home/europa/Documents/radar_system/python_app/runtime/s21_calibration_bundle.bin"
+      },
+      "reference": {
+        "set_name": "smoke_ref",
+        "bundle_path": "/home/europa/Documents/radar_system/python_app/runtime/s21_reference_bundle.bin"
+      }
+    },
+    "s11": {
+      "calibration": {
+        "open": {
+          "set_name": "smoke_open",
+          "bundle_path": "/home/europa/Documents/radar_system/python_app/runtime/s11_open_calibration_bundle.bin"
+        },
+        "short": {
+          "set_name": "smoke_short",
+          "bundle_path": "/home/europa/Documents/radar_system/python_app/runtime/s11_short_calibration_bundle.bin"
+        },
+        "load": {
+          "set_name": "smoke_load",
+          "bundle_path": "/home/europa/Documents/radar_system/python_app/runtime/s11_load_calibration_bundle.bin"
+        }
+      },
+      "reference": {
+        "set_name": "smoke_s11_ref",
+        "bundle_path": "/home/europa/Documents/radar_system/python_app/runtime/s11_reference_bundle.bin"
+      }
+    }
   },
   "gpr": {
     "mode": "point",
@@ -122,29 +176,29 @@
   },
   "rings": {
     "raw": {
-      "name": "/radar_raw_smoke_1703912_791574940686872",
-      "capacity": 32,
+      "name": "/radar_raw_smoke_2_20242576200473",
+      "capacity": 50,
       "slot_size_bytes": 2097152
     },
     "raw_tap": {
-      "name": "/radar_raw_tap_smoke_1703912_791574940693657",
-      "capacity": 32,
+      "name": "/radar_raw_tap_smoke_2_20242576209903",
+      "capacity": 50,
       "slot_size_bytes": 2097152
     },
     "preprocessed": {
-      "name": "/radar_preprocessed_smoke_1703912_791574940694423",
-      "capacity": 32,
+      "name": "/radar_preprocessed_smoke_2_20242576212225",
+      "capacity": 50,
       "slot_size_bytes": 2097152
     },
     "preprocessed_tap": {
-      "name": "/radar_preprocessed_tap_smoke_1703912_791574940694970",
-      "capacity": 32,
+      "name": "/radar_preprocessed_tap_smoke_2_20242576213549",
+      "capacity": 50,
       "slot_size_bytes": 2097152
     },
     "results": {
-      "name": "/radar_results_smoke_1703912_791574940696951",
-      "capacity": 32,
+      "name": "/radar_results_smoke_2_20242576214682",
+      "capacity": 50,
       "slot_size_bytes": 2097152
     }
   }
-}
+}
\ No newline at end of file
diff --git a/python_app/runtime/s11_load_calibration_bundle.bin b/python_app/runtime/s11_load_calibration_bundle.bin
new file mode 100644
index 0000000..1fa318e
Binary files /dev/null and b/python_app/runtime/s11_load_calibration_bundle.bin differ
diff --git a/python_app/runtime/s11_open_calibration_bundle.bin b/python_app/runtime/s11_open_calibration_bundle.bin
new file mode 100644
index 0000000..3484277
Binary files /dev/null and b/python_app/runtime/s11_open_calibration_bundle.bin differ
diff --git a/python_app/runtime/s11_reference_bundle.bin b/python_app/runtime/s11_reference_bundle.bin
new file mode 100644
index 0000000..5722cae
Binary files /dev/null and b/python_app/runtime/s11_reference_bundle.bin differ
diff --git a/python_app/runtime/s11_short_calibration_bundle.bin b/python_app/runtime/s11_short_calibration_bundle.bin
new file mode 100644
index 0000000..0a5c029
Binary files /dev/null and b/python_app/runtime/s11_short_calibration_bundle.bin differ
diff --git a/python_app/runtime/s21_calibration_bundle.bin b/python_app/runtime/s21_calibration_bundle.bin
new file mode 100644
index 0000000..7917932
Binary files /dev/null and b/python_app/runtime/s21_calibration_bundle.bin differ
diff --git a/python_app/runtime/s21_reference_bundle.bin b/python_app/runtime/s21_reference_bundle.bin
new file mode 100644
index 0000000..415b014
Binary files /dev/null and b/python_app/runtime/s21_reference_bundle.bin differ
diff --git a/python_app/scripts/check_snapshot_numpy.py b/python_app/scripts/check_snapshot_numpy.py
index d1b2524..2da91c7 100644
--- a/python_app/scripts/check_snapshot_numpy.py
+++ b/python_app/scripts/check_snapshot_numpy.py
@@ -46,12 +46,22 @@ def _all_traces_from_raw_or_pre(collection_dir: Path) -> list[tuple[np.ndarray,
             raise ValueError(f"Invalid trace record in {collection_dir / 'meta.json'}")
 
         freq_file = str(trace_meta.get("freq_file", ""))
+        s11_file = str(trace_meta.get("s11_file", ""))
         s21_file = str(trace_meta.get("s21_file", ""))
         freq = np.load(collection_dir / freq_file)
+        s11 = np.load(collection_dir / s11_file)
         s21 = np.load(collection_dir / s21_file)
+        if freq.shape != s11.shape:
+            raise ValueError(f"Shape mismatch freq/s11 in {collection_dir}")
         if freq.shape != s21.shape:
             raise ValueError(f"Shape mismatch freq/s21 in {collection_dir}")
-        if not (np.isfinite(freq).all() and np.isfinite(np.real(s21)).all() and np.isfinite(np.imag(s21)).all()):
+        if not (
+            np.isfinite(freq).all()
+            and np.isfinite(np.real(s11)).all()
+            and np.isfinite(np.imag(s11)).all()
+            and np.isfinite(np.real(s21)).all()
+            and np.isfinite(np.imag(s21)).all()
+        ):
             raise ValueError(f"Non-finite values in {collection_dir}")
 
         label = f"i{int(trace_meta.get('input', 0))}_o{int(trace_meta.get('output', 0))}"
diff --git a/python_app/scripts/manual_smoke_run.py b/python_app/scripts/manual_smoke_run.py
index a9b1107..42a306f 100644
--- a/python_app/scripts/manual_smoke_run.py
+++ b/python_app/scripts/manual_smoke_run.py
@@ -49,7 +49,13 @@ def _shm_unlink(name: str) -> None:
         raise OSError(err, f"shm_unlink failed for {name}")
 
 
-def build_synthetic_collection(config: RunConfigModel, value_scale: float) -> SweepCollection:
+def build_synthetic_collection(
+    config: RunConfigModel,
+    value_scale: float,
+    *,
+    s11_scale: float,
+    s11_phase_offset: float,
+) -> SweepCollection:
     """Build synthetic sweep collection for all configured switch combos."""
     traces: list[TraceData] = []
     combos = RunConfigModel.build_full_combos(config.input_switch.positions, config.output_switch.positions)
@@ -62,12 +68,15 @@ def build_synthetic_collection(config: RunConfigModel, value_scale: float) -> Sw
             dtype=np.float32,
         )
         phase = np.linspace(0.0, np.pi * 2.0, config.radar.sweep.points, dtype=np.float32)
+        reflected_phase = (phase * 0.6) + s11_phase_offset
+        s11 = (s11_scale * (np.cos(reflected_phase) + 1j * np.sin(reflected_phase))).astype(np.complex64)
         s21 = value_scale * (np.cos(phase) + 1j * np.sin(phase)).astype(np.complex64)
 
         traces.append(
             TraceData(
                 combo=ComboKey(input_pos=combo.input, output_pos=combo.output),
                 frequency_hz=frequency_hz,
+                s11=s11,
                 s21=s21,
             )
         )
@@ -107,22 +116,27 @@ def main() -> int:
         power_dbm=config.radar.sweep.power_dbm,
     )
 
-    calibration_set = build_synthetic_collection(config, value_scale=1.0)
-    reference_set = build_synthetic_collection(config, value_scale=0.3)
+    s21_calibration_set = build_synthetic_collection(config, value_scale=1.0, s11_scale=0.15, s11_phase_offset=0.4)
+    s21_reference_set = build_synthetic_collection(config, value_scale=0.3, s11_scale=0.08, s11_phase_offset=0.9)
+    s11_open_set = build_synthetic_collection(config, value_scale=0.85, s11_scale=0.95, s11_phase_offset=0.1)
+    s11_short_set = build_synthetic_collection(config, value_scale=0.85, s11_scale=0.95, s11_phase_offset=3.2)
+    s11_load_set = build_synthetic_collection(config, value_scale=0.85, s11_scale=0.05, s11_phase_offset=1.4)
+    s11_reference_set = build_synthetic_collection(config, value_scale=0.3, s11_scale=0.18, s11_phase_offset=1.1)
 
-    store.save_set("calibration", radar_key, "smoke_cal", calibration_set)
-    store.save_set("reference", radar_key, "smoke_ref", reference_set)
+    store.save_set("s21_calibration", radar_key, "smoke_cal", s21_calibration_set)
+    store.save_set("s21_reference", radar_key, "smoke_ref", s21_reference_set)
+    store.save_set("s11_open", radar_key, "smoke_open", s11_open_set)
+    store.save_set("s11_short", radar_key, "smoke_short", s11_short_set)
+    store.save_set("s11_load", radar_key, "smoke_load", s11_load_set)
+    store.save_set("s11_reference", radar_key, "smoke_s11_ref", s11_reference_set)
 
-    calibration_bundle, reference_bundle = config_writer.prepare_s21_bundles(
-        store,
-        radar_key,
-        "smoke_cal",
-        "smoke_ref",
-    )
-    config.preprocess.s21_calibration_set = "smoke_cal"
-    config.preprocess.s21_reference_set = "smoke_ref"
-    config.preprocess.s21_calibration_bundle_path = str(calibration_bundle)
-    config.preprocess.s21_reference_bundle_path = str(reference_bundle)
+    config.preprocess.s21.calibration.set_name = "smoke_cal"
+    config.preprocess.s21.reference.set_name = "smoke_ref"
+    config.preprocess.s11.calibration.open.set_name = "smoke_open"
+    config.preprocess.s11.calibration.short.set_name = "smoke_short"
+    config.preprocess.s11.calibration.load.set_name = "smoke_load"
+    config.preprocess.s11.reference.set_name = "smoke_s11_ref"
+    config_writer.prepare_preprocess_bundles(store, radar_key, config)
 
     config_path = config_writer.write(config, project_root / "python_app/runtime/run_config_smoke.json")
 
diff --git a/python_app/storage/npz/serialize.py b/python_app/storage/npz/serialize.py
index 5ee4df0..855f5a6 100644
--- a/python_app/storage/npz/serialize.py
+++ b/python_app/storage/npz/serialize.py
@@ -28,13 +28,12 @@ def serialize_trace_collection(collection: SweepCollection, magic: int) -> bytes
 
     for trace in collection.traces:
         freq = np.asarray(trace.frequency_hz, dtype=np.float32)
+        s11 = np.asarray(trace.s11, dtype=np.complex64)
         s21 = np.asarray(trace.s21, dtype=np.complex64)
+        if freq.size != s11.size:
+            raise ValueError("Trace frequency and S11 sizes must match")
         if freq.size != s21.size:
             raise ValueError("Trace frequency and S21 sizes must match")
-        # Python workflows still operate on S21 only. Emit a zero-filled S11
-        # channel so C++ trace bundles keep the same wire format as runtime
-        # rings while the Python layer remains unchanged.
-        s11 = np.zeros(freq.size, dtype=np.complex64)
 
         buffer.extend(struct.pack("<III", trace.combo.input_pos, trace.combo.output_pos, int(freq.size)))
         buffer.extend(freq.astype("<f4", copy=False).tobytes())
diff --git a/python_app/storage/npz/snapshot_numpy.py b/python_app/storage/npz/snapshot_numpy.py
index 6f71ed0..162efd8 100644
--- a/python_app/storage/npz/snapshot_numpy.py
+++ b/python_app/storage/npz/snapshot_numpy.py
@@ -157,8 +157,10 @@ def save_trace_history_numpy(stage_dir: Path, history: list[SweepCollection]) ->
         for trace in collection.traces:
             tag = f"i{trace.combo.input_pos}_o{trace.combo.output_pos}"
             freq = np.asarray(trace.frequency_hz, dtype=np.float32)
+            s11 = np.asarray(trace.s11, dtype=np.complex64)
             s21 = np.asarray(trace.s21, dtype=np.complex64)
             np.save(collection_dir / f"{tag}_freq.npy", freq)
+            np.save(collection_dir / f"{tag}_s11.npy", s11)
             np.save(collection_dir / f"{tag}_s21.npy", s21)
             traces_meta.append(
                 {
@@ -166,6 +168,7 @@ def save_trace_history_numpy(stage_dir: Path, history: list[SweepCollection]) ->
                     "output": int(trace.combo.output_pos),
                     "points": int(freq.size),
                     "freq_file": f"{tag}_freq.npy",
+                    "s11_file": f"{tag}_s11.npy",
                     "s21_file": f"{tag}_s21.npy",
                 }
             )
diff --git a/python_app/storage/npz/store.py b/python_app/storage/npz/store.py
index c614f07..b68b38e 100644
--- a/python_app/storage/npz/store.py
+++ b/python_app/storage/npz/store.py
@@ -24,7 +24,7 @@ from python_app.storage.store_api import StoreApi
 
 
 class NpzStore(StoreApi):
-    """Persist calibration/reference sets and runtime snapshots using NumPy files."""
+    """Persist preprocess sets and runtime snapshots using NumPy files."""
 
     def __init__(self, root_dir: Path) -> None:
         """Create store rooted at `root_dir`."""
@@ -32,7 +32,7 @@ class NpzStore(StoreApi):
         self._root_dir.mkdir(parents=True, exist_ok=True)
 
     def save_set(self, kind: str, radar_key: str, set_name: str, collection: SweepCollection) -> None:
-        """Persist named calibration/reference set as NPZ and metadata JSON."""
+        """Persist named preprocess set as NPZ and metadata JSON."""
         set_dir = self._set_dir(kind, radar_key)
         set_dir.mkdir(parents=True, exist_ok=True)
 
@@ -45,14 +45,17 @@ class NpzStore(StoreApi):
         for trace in collection.traces:
             suffix = f"i{trace.combo.input_pos}_o{trace.combo.output_pos}"
             freq_key = f"freq_{suffix}"
+            s11_key = f"s11_{suffix}"
             s21_key = f"s21_{suffix}"
             payload[freq_key] = np.asarray(trace.frequency_hz, dtype=np.float32)
+            payload[s11_key] = np.asarray(trace.s11, dtype=np.complex64)
             payload[s21_key] = np.asarray(trace.s21, dtype=np.complex64)
             combo_records.append(
                 {
                     "input": trace.combo.input_pos,
                     "output": trace.combo.output_pos,
                     "freq_key": freq_key,
+                    "s11_key": s11_key,
                     "s21_key": s21_key,
                 }
             )
@@ -66,7 +69,7 @@ class NpzStore(StoreApi):
         meta_path.write_text(json.dumps(meta, indent=2), encoding="utf-8")
 
     def load_set(self, kind: str, radar_key: str, set_name: str) -> SweepCollection:
-        """Load named calibration/reference set from NPZ representation."""
+        """Load named preprocess set from NPZ representation."""
         set_dir = self._set_dir(kind, radar_key)
         npz_path = set_dir / f"{set_name}.npz"
         meta_path = set_dir / f"{set_name}.json"
@@ -80,11 +83,13 @@ class NpzStore(StoreApi):
         traces: list[TraceData] = []
         for combo in meta["combos"]:
             freq = np.asarray(arrays[combo["freq_key"]], dtype=np.float32)
+            s11 = np.asarray(arrays[combo["s11_key"]], dtype=np.complex64)
             s21 = np.asarray(arrays[combo["s21_key"]], dtype=np.complex64)
             traces.append(
                 TraceData(
                     combo=ComboKey(input_pos=int(combo["input"]), output_pos=int(combo["output"])),
                     frequency_hz=freq,
+                    s11=s11,
                     s21=s21,
                 )
             )
diff --git a/python_app/storage/store_api.py b/python_app/storage/store_api.py
index e52d838..4fbd374 100644
--- a/python_app/storage/store_api.py
+++ b/python_app/storage/store_api.py
@@ -1,4 +1,4 @@
-"""Abstract storage API for calibration/reference sets."""
+"""Abstract storage API for preprocess sets."""
 
 from __future__ import annotations
 
diff --git a/python_app/workflows/calibration_workflow.py b/python_app/workflows/calibration_workflow.py
index 0eaa3cf..3d00981 100644
--- a/python_app/workflows/calibration_workflow.py
+++ b/python_app/workflows/calibration_workflow.py
@@ -54,12 +54,13 @@ def capture_calibration_set(
             if config.runtime.settling_ms > 0:
                 time.sleep(config.runtime.settling_ms / 1000.0)
 
-            frequency_hz, s21 = radar.acquire_s21()
+            sweep = radar.acquire()
             traces.append(
                 TraceData(
                     combo=ComboKey(input_pos=combo.input, output_pos=combo.output),
-                    frequency_hz=frequency_hz,
-                    s21=s21,
+                    frequency_hz=sweep.x,
+                    s11=sweep.trace("s11"),
+                    s21=sweep.trace("s21"),
                 )
             )
     finally:
@@ -77,5 +78,5 @@ def capture_calibration_set(
         ifbw_hz=config.radar.sweep.if_bandwidth_hz,
         power_dbm=config.radar.sweep.power_dbm,
     )
-    store.save_set("calibration", radar_key, set_name, collection)
+    store.save_set("s21_calibration", radar_key, set_name, collection)
     return radar_key, collection
diff --git a/python_app/workflows/reference_workflow.py b/python_app/workflows/reference_workflow.py
index 0915936..5002573 100644
--- a/python_app/workflows/reference_workflow.py
+++ b/python_app/workflows/reference_workflow.py
@@ -54,12 +54,13 @@ def capture_reference_set(
             if config.runtime.settling_ms > 0:
                 time.sleep(config.runtime.settling_ms / 1000.0)
 
-            frequency_hz, s21 = radar.acquire_s21()
+            sweep = radar.acquire()
             traces.append(
                 TraceData(
                     combo=ComboKey(input_pos=combo.input, output_pos=combo.output),
-                    frequency_hz=frequency_hz,
-                    s21=s21,
+                    frequency_hz=sweep.x,
+                    s11=sweep.trace("s11"),
+                    s21=sweep.trace("s21"),
                 )
             )
     finally:
@@ -77,5 +78,5 @@ def capture_reference_set(
         ifbw_hz=config.radar.sweep.if_bandwidth_hz,
         power_dbm=config.radar.sweep.power_dbm,
     )
-    store.save_set("reference", radar_key, set_name, collection)
+    store.save_set("s21_reference", radar_key, set_name, collection)
     return radar_key, collection
diff --git a/python_app/workflows/sequential_capture_workflow.py b/python_app/workflows/sequential_capture_workflow.py
index 3910c72..525842c 100644
--- a/python_app/workflows/sequential_capture_workflow.py
+++ b/python_app/workflows/sequential_capture_workflow.py
@@ -1,4 +1,4 @@
-"""Sequential capture workflow for calibration/reference dataset creation."""
+"""Sequential capture workflow for preprocess asset dataset creation."""
 
 from __future__ import annotations
 
@@ -6,6 +6,8 @@ from contextlib import suppress
 from dataclasses import dataclass
 import time
 
+import numpy as np
+
 from python_app.hardware_full.librevna_service import LibreVnaService
 from python_app.hardware_full.switch_service import SwitchService
 from python_app.models.dataset_model import ComboKey, SweepCollection, TraceData
@@ -28,8 +30,8 @@ class SequentialCaptureSession:
     """Manage hardware and switch stepping for full combo capture sequence."""
 
     def __init__(self, config: RunConfigModel, kind: str, set_name: str) -> None:
-        """Create capture session for a calibration or reference set."""
-        if kind not in {"calibration", "reference"}:
+        """Create capture session for one preprocess asset set."""
+        if kind not in {"s21_calibration", "s21_reference", "s11_open", "s11_short", "s11_load", "s11_reference"}:
             raise RuntimeError(f"Unsupported capture kind: {kind}")
         if not set_name:
             raise RuntimeError("Set name is required")
@@ -69,7 +71,7 @@ class SequentialCaptureSession:
 
     @property
     def kind(self) -> str:
-        """Return capture kind (`calibration` or `reference`)."""
+        """Return canonical preprocess asset key for this capture session."""
         return self._kind
 
     @property
@@ -125,11 +127,12 @@ class SequentialCaptureSession:
         if self._config.runtime.settling_ms > 0:
             time.sleep(self._config.runtime.settling_ms / 1000.0)
 
-        frequency_hz, s21 = self._radar.acquire_s21()
+        sweep = self._radar.acquire()
         trace = TraceData(
             combo=ComboKey(input_pos=combo.input, output_pos=combo.output),
-            frequency_hz=frequency_hz,
-            s21=s21,
+            frequency_hz=np.asarray(sweep.x, dtype=np.float32),
+            s11=np.asarray(sweep.trace("s11"), dtype=np.complex64),
+            s21=np.asarray(sweep.trace("s21"), dtype=np.complex64),
         )
         self._traces.append(trace)
         self._next_index += 1
diff --git a/run_config.json b/run_config.json
index 0bf5510..752c74a 100644
--- a/run_config.json
+++ b/run_config.json
@@ -55,14 +55,36 @@
     ]
   },
   "preprocess": {
-    "s21_calibration_set": "",
-    "s21_reference_set": "",
-    "s21_calibration_bundle_path": "python_app/runtime/s21_calibration_bundle.bin",
-    "s21_reference_bundle_path": "python_app/runtime/s21_reference_bundle.bin",
-    "s11_open_calibration_bundle_path": "",
-    "s11_short_calibration_bundle_path": "",
-    "s11_load_calibration_bundle_path": "",
-    "s11_reference_bundle_path": ""
+    "s21": {
+      "calibration": {
+        "set_name": "",
+        "bundle_path": ""
+      },
+      "reference": {
+        "set_name": "",
+        "bundle_path": ""
+      }
+    },
+    "s11": {
+      "calibration": {
+        "open": {
+          "set_name": "",
+          "bundle_path": ""
+        },
+        "short": {
+          "set_name": "",
+          "bundle_path": ""
+        },
+        "load": {
+          "set_name": "",
+          "bundle_path": ""
+        }
+      },
+      "reference": {
+        "set_name": "",
+        "bundle_path": ""
+      }
+    }
   },
   "gpr": {
     "mode": "point",