Update backend/comm_system.py

backend/comm_system.py

@@ -1,25 +1,25 @@
-import numpy as np
+import random
 
-def simulate_channel(snr_db: float, num_symbols: int = 200):
-    # 1. Generate 16-QAM Constellation points (+/-1, +/-3)
-    constellation = np.array([complex(i, j) for i in [-3, -1, 1, 3] for j in [-3, -1, 1, 3]])
+def simulate_channel(text: str, error_rate: float = 0.15) -> str:
+    """
+    Simulates a noisy 6G wireless channel.
+    It randomly destroys characters based on the error_rate probability.
+    """
+    if not text:
+        return ""
+        
+    corrupted_message = []
+    # These are the 'static' symbols that replace your text when the signal drops
+    noise_symbols = "!@#$%^&*~?"
     
-    # 2. Transmit ideal symbols
-    ideal_symbols = np.random.choice(constellation, num_symbols)
-    
-    # 3. Probability Math: Calculate noise power based on SNR limit
-    signal_power = np.mean(np.abs(constellation)**2) # Avg power of 16-QAM
-    snr_linear = 10 ** (snr_db / 10)
-    noise_power = signal_power / snr_linear
-    
-    # 4. Inject Gaussian Noise (AWGN)
-    noise = np.sqrt(noise_power / 2) * (np.random.randn(num_symbols) + 1j * np.random.randn(num_symbols))
-    noisy_symbols = ideal_symbols + noise
-    
-    # Return data formatted for the React UI Plotly graph
-    return {
-        "ideal_i": ideal_symbols.real.tolist(),
-        "ideal_q": ideal_symbols.imag.tolist(),
-        "noisy_i": noisy_symbols.real.tolist(),
-        "noisy_q": noisy_symbols.imag.tolist()
-    }
+    for char in text:
+        # Use probability to decide if this specific character survives the transmission
+        if random.random() < error_rate and char != " ":
+            # The signal dropped! Replace the letter with a random noise symbol
+            corrupted_message.append(random.choice(noise_symbols))
+        else:
+            # The signal survived! Keep the original letter
+            corrupted_message.append(char)
+            
+    # Join the pieces back together into a single string
+    return "".join(corrupted_message)