Fixed noise generation

recording_generation.py

@@ -61,7 +61,7 @@ class RecordingGenerator:
     def generate_wb(self, num: int = 2, length: int = 8192):
         for i in range(num):
             recording = create_noise_recording(
-                length=length, rms_power=0.2, counter=random.choice([2, 4, 8, 16, 32])
+                length=length, rms_power=0.2, seed=num
             )
             recording.to_npy(filename=f"wb{i + 1}", overwrite=True)
             print(f"wb{i + 1} file saved.")

signal_generation.py

@@ -99,24 +99,23 @@ def create_lfm_recording(
 def create_noise_recording(
     rms_power: float,
     length: int,
-    counter: int,
+    seed: int | None = None
 ) -> Recording:
     """Generate a Recording of Additive White Gaussian Noise (AWGN)."""
     # 1. Create a repeating pseudo-random envelope
-    np.random.seed(256 + counter)
-    chunk = np.random.rand(length // 4)
-    tiled = np.tile(chunk, 4)
-    amplitude_envelope = np.sqrt(tiled)
+    if seed is not None:
+        np.random.seed(seed)
+    
+    # 2. Sigma for complex AWGN:
+    sigma = np.sqrt(rms_power / 2)
 
-    # 2. Generate complex Gaussian noise with unit power
-    real = np.random.normal(0, 1, length)
-    imag = np.random.normal(0, 1, length)
+    # 3. Generate complex Gaussian noise with correct power
+    real = np.random.normal(0, sigma, length)
+    imag = np.random.normal(0, sigma, length)
     complex_noise = real + 1j * imag
 
-    # 3. Scale noise by desired power and envelope
-    scaled_noise = complex_noise * amplitude_envelope * np.sqrt(rms_power)
-    metadata = {"interference": "wb", "signal_type": "noise"}
-    return Recording(data=scaled_noise, metadata=metadata)
+    metadata = {"interference": "wb", "signal_type": "noise", "rms_power": rms_power}
+    return Recording(data=complex_noise, metadata=metadata)
 
 
 def create_ctnb_recording(length: int) -> Recording: