Add RFG UDP source to rph_radar

README.md

@@ -19,7 +19,8 @@ skips overwritten frames and continues from the retained tail:
 
 1. **Acquisition** — Python producers configure the radar, acquire frequency sweeps,
    and publish raw S21 traces. Both single and multi-device LibreVNA use
-   `matrix_raw_producer`; RadioPhotonic radar (RPH) uses `rph_radar_raw_producer` with its C++ collector.
+   `matrix_raw_producer`; RadioPhotonic radar (RPH) uses `rph_radar_raw_producer` with its C++
+   collector (E-502) or the RFG board's UDP stream.
 2. **Preprocessing** — `data_preprocessor` applies through calibration,
    reference subtraction, optional frequency-domain notch filtering, and an
    optional object-based MIMO correction of S21.
@@ -47,9 +48,18 @@ controls, processing settings and a copy of the live plot through an embedded we
 - **librevna_multi** — synchronized multi-device LibreVNA.
 - **rph_radar** — [RadioPhotonic radar (RPH) collector](data_acq_and_processing/rph_radar_collector/README.md),
   with manual laser setpoints or LD1 current variation via **Apply Radar**.
-  The application owns the collector and exchanges complete sweeps over a PTY.
-  Switching to a different antenna pair starts a fresh ADC session after settling;
-  queued samples and an initial partial sweep are discarded before using that pair.
+  `radar.rph_radar.source` selects the ADC:
+  - `e502` (default) — the application owns the collector and exchanges complete
+    sweeps over a PTY. Switching to a different antenna pair starts a fresh ADC session
+    after settling, discarding queued samples and an initial partial sweep.
+  - `rfg_udp` — the RFG board sends averaged sweep points to `udp_bind`
+    (`run_config_rph_radar_rfg.example.json`); main = ch0 − ch1, reference = ch2. It
+    needs `laser_control.mode: variation` (even when the laser is started elsewhere):
+    a sweep must have exactly the task's step count, `ceil((max − min) / step)` in DAC
+    codes, with no lost points; others are dropped (the board loses a few percent).
+    Capture windows come from kernel receive timestamps. Only one antenna pair (both
+    switches with one position): without a source-side marker a sweep after a switch
+    cannot be proven fresh.
 - **mock / simulator** — driver-less mode for development without hardware.
 
 ## Processing modes
@@ -123,7 +133,7 @@ python3 -m venv .venv
 .venv/bin/python -m pip install --upgrade pip
 .venv/bin/python -m pip install -r requirements.txt
 make                     # data_preprocessor and data_processor in build/bin/
-make rph_radar_collector  # also required for RadioPhotonic radar (RPH) acquisition
+make rph_radar_collector  # RadioPhotonic radar (RPH) with radar.rph_radar.source: e502
 ```
 
 `make` builds the sar3d GPU code when it finds CUDA (see Requirements) and
@@ -360,7 +370,8 @@ measurement key and are not selected by the renamed mode.
 
 ### RPH phase calibration
 
-Use `run_config_examples/run_config_rph_radar.example.json` for **RadioPhotonic radar (RPH)**.
+Use `run_config_examples/run_config_rph_radar.example.json` (E-502) or
+`run_config_rph_radar_rfg.example.json` (RFG board) for **RadioPhotonic radar (RPH)**.
 Apply the desired laser settings with **Apply Radar**, then stop acquisition before
 running the calibration tool: