Merge pull request #111 from Genaker/rtl-sdr

rtl and display radio packet

lib/config/config.h

@@ -50,7 +50,7 @@ struct Config
           listen_on_serial0(String("none")), listen_on_serial1(String("readline")),
           listen_on_usb(String("readline")), rx_lora(NULL), tx_lora(NULL),
           // Enable Lora Send:
-          // rx_lora(configureLora("freq:920")),tx_lora(configureLora("freq:916"))
+          // rx_lora(configureLora("freq:920")), tx_lora(configureLora("freq:916")),
           is_host(false) {};
 
     bool write_config(const char *path);

rtl/install-macos.sh

@@ -0,0 +1,3 @@
+brew update
+brew install rtl-sdr
+rtl_test

rtl/rtl-scanner.py

@@ -0,0 +1,98 @@
+import numpy as np
+from rtlsdr import RtlSdr
+import time
+import os
+
+def ascii_bar_chart(data, start_freq, step, max_height=20, symbol='#'):
+    """
+    Converts an array of RSSI values into an ASCII vertical bar chart with RSSI labels on the left and MHz labels under every 5th step.
+    """
+    min_rssi = min(data)
+    max_rssi = max(data)
+    normalized = [(x - min_rssi) / (max_rssi - min_rssi + 1e-6) for x in data]  # Normalize to 0-1
+    heights = [int(value * max_height) for value in normalized]
+    
+    # Generate left-aligned RSSI labels
+    rssi_range = np.linspace(max_rssi, min_rssi, max_height)
+    rssi_labels = [f"{rssi:.1f} dB".rjust(8) for rssi in rssi_range]
+
+    # Print the vertical bars with RSSI labels
+    for level, label in zip(range(max_height, 0, -1), rssi_labels):
+        line = label + ' '  # Add RSSI label
+        for height in heights:
+            line += symbol if height >= level else ' '
+        print(line)
+    
+    # Print x-axis
+    freq_labels = [f"{(start_freq + step * i) / 1e6:.0f}" if i % 5 == 0 else "" for i in range(len(data))]
+    print(" " * 8 + '-' * len(data))  # Bar separator
+    x_axis = " " * 8
+    printed = 0
+    previous_label = ""
+    for i, label in enumerate(freq_labels):
+        if label:
+            printed = 0
+            previous_label = label
+            x_axis += label #.center(1)  # Center the MHz label under the bar
+        else:
+            if printed < (5 - len(previous_label)):
+                x_axis += " "  # No space between bars
+            printed += 1
+    print(x_axis)
+
+def scan_frequency_range(start_freq, end_freq, step, sdr, fft_size=2*1024):
+    """
+    Scans a frequency range using an RTL-SDR device and calculates RSSI for each frequency.
+    """
+    center_frequencies = np.arange(start_freq, end_freq + step, step)
+    rssi_values = []
+    
+    for freq in center_frequencies:
+        sdr.center_freq = freq
+        samples = sdr.read_samples(fft_size)
+        
+        # Perform FFT and calculate RSSI
+        power_spectrum = np.abs(np.fft.fft(samples))**2
+        power_db = 10 * np.log10(power_spectrum + 1e-6)  # Convert to dB
+        avg_rssi = np.percentile(power_db, 90)  # 95 percentile RSSI for this frequency
+        rssi_values.append(avg_rssi)
+    
+    return rssi_values
+
+def main():
+    # Frequency range in Hz
+    start_freq = 800e6  # 800 MHz
+    end_freq = 900e6   # 1200 MHz
+    step = 1e6          # 1 MHz steps
+
+    # Initialize RTL-SDR
+    sdr = RtlSdr()
+    sdr.sample_rate = 2.048e6  # 2.048 MSPS
+    sdr.gain = 10             # Adjust gain as needed
+
+    try:
+        while True:
+            start_time = time.time()
+            rssi_values = scan_frequency_range(start_freq, end_freq, step, sdr)
+            end_time = time.time()
+
+            # Clear screen
+            os.system('clear' if os.name == 'posix' else 'cls')
+
+            # Scan frequency range
+            print(f"Scanning range: {start_freq / 1e6:.0f} MHz to {end_freq / 1e6:.0f} MHz")
+            print(f"Scanning time: {end_time - start_time:.2f} seconds")
+
+            # Display ASCII bar chart with RSSI and MHz labels
+            print("RSSI (dB):")
+            ascii_bar_chart(rssi_values, start_freq, step)
+            #time.sleep(0.5)  # Refresh every 0.5 seconds
+
+    except KeyboardInterrupt:
+        print("\nStopping scan...")
+
+    finally:
+        sdr.close()
+
+if __name__ == '__main__':
+    main()

src/main.cpp

@@ -153,6 +153,8 @@ typedef enum
 // String SCAN_RANGES = String("850..890,920..950");
 String SCAN_RANGES = "";
 
+std::unordered_map<int, bool> ignoredFreq = {/*{916, true}, {915, true}*/};
+
 size_t scan_pages_sz = 0;
 ScanPage *scan_pages;
 size_t scan_page = 0;
@@ -1686,10 +1688,18 @@ void doScan()
                 }
                 else
                     g = &getRSSI;
-
-                uint16_t max_rssi = r.rssiMethod(g, &r, samples, result,
-                                                 RADIOLIB_SX126X_SPECTRAL_SCAN_RES_SIZE);
-
+                uint16_t max_rssi = 120;
+                // Scan if not in the ignore list
+                if (ignoredFreq.find((int)r.current_frequency) == ignoredFreq.end())
+                {
+                    max_rssi = r.rssiMethod(g, &r, samples, result,
+                                            RADIOLIB_SX126X_SPECTRAL_SCAN_RES_SIZE);
+                }
+                else
+                {
+                    // if ignored default RSSI value -120dB
+                    max_rssi = 120;
+                }
                 if (max_x_rssi[display_x] > max_rssi)
                 {
                     max_x_rssi[display_x] = max_rssi;
@@ -1961,6 +1971,33 @@ void doScan()
 #endif
 }
 
+std::unordered_map<int, int> previousPac = {/*{916, true}, {915, true}*/};
+
+std::unordered_map<int, int16_t> findMaxRssi(int16_t *rssis, uint32_t *freqs_khz,
+                                             int dump_sz, int level = 80)
+{
+    std::unordered_map<int, int16_t> maxRssiPerMHz; // Map to store max RSSI per MHz
+
+    for (int i = 0; i < dump_sz; i++)
+    {
+        int16_t rssi = rssis[i];
+        int freq_mhz = (int)freqs_khz[i] / 1000; // Convert kHz to MHz
+
+        // Update the maximum RSSI for this MHz frequency
+        if (maxRssiPerMHz.find(freq_mhz) == maxRssiPerMHz.end() ||
+            maxRssiPerMHz[freq_mhz] < rssi)
+        {
+            if (abs(rssi) < level)
+            {
+                maxRssiPerMHz[freq_mhz] = rssi;
+            }
+        }
+    }
+
+    return maxRssiPerMHz;
+}
+
+bool lock = false;
 int16_t checkRadio(RadioComms &comms)
 {
     radioIsScan = false;
@@ -1971,7 +2008,7 @@ int16_t checkRadio(RadioComms &comms)
     Message *msg = comms.receive(
         config.is_host
             ? 2000
-            : 200); // 200ms should be enough to receive 500 bytes at SF 7 and BW 500
+            : 500); // 200ms should be enough to receive 500 bytes at SF 7 and BW 500
     if (msg == NULL)
     {
         return status;
@@ -1979,6 +2016,49 @@ int16_t checkRadio(RadioComms &comms)
 
     if (msg->type == SCAN_RESULT)
     {
+        // if (lock == false)
+        {
+            lock = true;
+
+            // display.setDisplayRotation(1);
+            // display.println("Host Mode ->");
+
+            size_t dump_sz = msg->payload.dump.sz;
+            int16_t *rssi = msg->payload.dump.rssis;
+            uint32_t *fr = msg->payload.dump.freqs_khz;
+
+            std::unordered_map<int, int16_t> maxMhzRssi =
+                findMaxRssi(rssi, fr, dump_sz, 85);
+
+            int lx, ly, i = 0;
+            for (const auto &pair : maxMhzRssi)
+            {
+                if (i == 0 && maxMhzRssi.size() > 0)
+                {
+                    display.clear();
+                }
+                // screen overflow protection
+                if (lx < 130)
+                {
+                    int16_t rssi = pair.second;
+                    int16_t fr = (int)pair.first;
+                    display.drawString(lx, ly, String(fr) + ":" + String(rssi));
+                    // go to next line
+                    ly += 10;
+                    if (ly > 60)
+                    {
+                        ly = 0;
+
+                        // go to next column
+                        lx += 50;
+                    }
+                    display.display();
+                }
+                i++;
+            }
+            lock = false;
+        }
+
         HostComms->send(*msg);
     }
     else