diff --git a/software/gui.py b/software/gui.py
index 784794e..4bbc24a 100644
--- a/software/gui.py
+++ b/software/gui.py
@@ -10,7 +10,7 @@ from dataclasses import dataclass
 from PyQt6.QtCore import QProcess, QTimer
 from PyQt6.QtCore import QObject, QThread, pyqtSignal
 
-
+from PyQt6.QtCore import Qt
 import pyqtgraph as pg
 from PyQt6.QtWidgets import QApplication, QMainWindow
 
@@ -574,9 +574,23 @@ class MainWindow(QMainWindow):
         self.graph_widget.setLabel("bottom", "Sample")
         self.graph_widget.showGrid(x=True, y=True)
 
-        self.graph_curve = self.graph_widget.plot([])
+        self.graph_curve = self.graph_widget.plot(
+            [],
+            name="Data",
+        )
+
+        self.reference_curve = self.graph_widget.plot(
+            [],
+            name="Reference",
+        )
 
         self.graph_layout.addWidget(self.graph_widget)
+        self.graph_curve = self.graph_widget.plot([], pen=pg.mkPen(width=2))
+        self.reference_curve = self.graph_widget.plot(
+            [], pen=pg.mkPen(style=Qt.PenStyle.DashLine))
+
+        self.checkbox_draw_reference.stateChanged.connect(
+            self.update_reference_graph)
 
     def setup_network_settings(self):
         self._bind_spinbox_setting(
@@ -655,8 +669,8 @@ class MainWindow(QMainWindow):
     def on_data_received(self, data: list[int]):
         self.data = data
 
-        x = list(range(len(data)))
-        self.graph_curve.setData(x, data)
+        self.draw_main_graph()
+        self.update_reference_graph()
 
         if data:
             self.set_measurement_status(
@@ -684,6 +698,54 @@ class MainWindow(QMainWindow):
         if hasattr(self, "label_ping_status"):
             self.label_ping_status.setText(text)
 
+    def draw_main_graph(self):
+        if not self.data:
+            self.graph_curve.setData([])
+            return
+
+        x = list(range(len(self.data)))
+        self.graph_curve.setData(x, self.data)
+
+    def update_reference_graph(self):
+        """
+        Рисует или очищает эталонный график.
+        Вызывается после получения данных и при переключении checkbox_draw_reference.
+        """
+
+        if not self.checkbox_draw_reference.isChecked():
+            self.reference_curve.setData([])
+            return
+
+        if not self.data:
+            self.reference_curve.setData([])
+            return
+
+        reference_data = self.build_reference_data(len(self.data))
+
+        if not reference_data:
+            self.reference_curve.setData([])
+            return
+
+        x = list(range(len(reference_data)))
+        self.reference_curve.setData(x, reference_data)
+
+    def build_reference_data(self, length: int) -> list[int]:
+        """
+        Тут потом опишешь свою логику построения эталонного сигнала.
+
+        Главное: вернуть массив такой же или нужной тебе длины.
+        Например:
+            reference = [0] * length
+            reference[10:100] = ...
+            return reference
+        """
+
+        # TODO: сюда вставить свою логику эталонного графика
+
+        reference = [0] * length
+
+        return reference
+
 
 def main():
     app = QApplication(sys.argv)
diff --git a/software/reflectometer.ui b/software/reflectometer.ui
index 59e8de5..654da3c 100644
--- a/software/reflectometer.ui
+++ b/software/reflectometer.ui
@@ -23,7 +23,7 @@
       <item>
        <widget class="QTabWidget" name="tabWidget">
         <property name="currentIndex">
-         <number>0</number>
+         <number>1</number>
         </property>
         <widget class="QWidget" name="tab">
          <attribute name="title">
@@ -409,6 +409,13 @@
             </property>
            </widget>
           </item>
+          <item>
+           <widget class="QCheckBox" name="checkbox_draw_reference">
+            <property name="text">
+             <string>Отрисовка эталона</string>
+            </property>
+           </widget>
+          </item>
           <item>
            <spacer name="verticalSpacer_2">
             <property name="orientation">