Initial commit: project docs and ignore rules

ESP32-C5-Toolkit/main/signal_analysis.c

@@ -0,0 +1,104 @@
+#include "signal_analysis.h"
+#include "freertos/FreeRTOS.h"
+#include "freertos/semphr.h"
+#include "esp_timer.h"
+#include <string.h>
+#include <stdlib.h>
+
+#define MAX_CHANNELS 165
+#define MAX_HISTORY 100
+
+// Channel utilization tracking
+static channel_data_t channel_stats[MAX_CHANNELS];
+static SemaphoreHandle_t signal_mutex = NULL;
+
+// RSSI history tracking (per BSSID)
+typedef struct {
+    uint8_t bssid[6];
+    int8_t rssi_history[MAX_HISTORY];
+    uint32_t timestamps[MAX_HISTORY];
+    int head;
+    int count;
+} rssi_tracker_t;
+
+static rssi_tracker_t rssi_trackers[10];
+static int tracker_count = 0;
+
+void signal_update_packet(uint8_t channel, int8_t rssi) {
+    if (channel == 0 || channel > MAX_CHANNELS) {
+        return;
+    }
+    
+    if (signal_mutex == NULL) {
+        signal_mutex = xSemaphoreCreateMutex();
+        if (signal_mutex == NULL) {
+            return;
+        }
+    }
+    
+    if (xSemaphoreTake(signal_mutex, portMAX_DELAY) != pdTRUE) {
+        return;
+    }
+    
+    channel_data_t *ch = &channel_stats[channel - 1];
+    ch->channel = channel;
+    ch->packet_count++;
+    ch->rssi = (ch->rssi + rssi) / 2; // Average RSSI
+    ch->timestamp = (uint32_t)(esp_timer_get_time() / 1000000ULL);
+    
+    xSemaphoreGive(signal_mutex);
+}
+
+int signal_get_channel_utilization(channel_data_t *data, int max_channels) {
+    if (signal_mutex == NULL || data == NULL) {
+        return 0;
+    }
+    
+    if (xSemaphoreTake(signal_mutex, portMAX_DELAY) != pdTRUE) {
+        return 0;
+    }
+    
+    int count = 0;
+    for (int i = 0; i < MAX_CHANNELS && count < max_channels; i++) {
+        if (channel_stats[i].packet_count > 0) {
+            data[count++] = channel_stats[i];
+        }
+    }
+    
+    xSemaphoreGive(signal_mutex);
+    return count;
+}
+
+int signal_get_rssi_history(uint8_t *bssid, int8_t *rssi_history, uint32_t *timestamps, int max_samples) {
+    if (signal_mutex == NULL || bssid == NULL || rssi_history == NULL || timestamps == NULL) {
+        return 0;
+    }
+    
+    if (xSemaphoreTake(signal_mutex, portMAX_DELAY) != pdTRUE) {
+        return 0;
+    }
+    
+    // Find tracker for this BSSID
+    rssi_tracker_t *tracker = NULL;
+    for (int i = 0; i < tracker_count; i++) {
+        if (memcmp(rssi_trackers[i].bssid, bssid, 6) == 0) {
+            tracker = &rssi_trackers[i];
+            break;
+        }
+    }
+    
+    if (!tracker) {
+        xSemaphoreGive(signal_mutex);
+        return 0;
+    }
+    
+    int samples = (tracker->count < max_samples) ? tracker->count : max_samples;
+    for (int i = 0; i < samples; i++) {
+        int idx = (tracker->head - tracker->count + i + MAX_HISTORY) % MAX_HISTORY;
+        rssi_history[i] = tracker->rssi_history[idx];
+        timestamps[i] = tracker->timestamps[idx];
+    }
+    
+    xSemaphoreGive(signal_mutex);
+    return samples;
+}