Goouuu Tech GT-U16 RTK L1 + L5 GPS Module avec arduino – Interfaçage et analyse GNSS Données

#define GPSSerial  Serial
#define DEBUGSerial Serial

void setup()  
{
 GPSSerial.begin(115200);      
 DEBUGSerial.begin(115200);  
 DEBUGSerial.println("Waiting for GNSS data...");
}

void loop()  
{
 while (GPSSerial.available()) {  
    DEBUGSerial.write(GPSSerial.read());
 }
}

#define GPSSerial   Serial
#define DEBUGSerial Serial
const unsigned long PRINT_INTERVAL = 1000;
// GNSS Data
String utcTime = "--:--:--";
String localTime = "--:--:--";
String latitude = "--";
String longitude = "--";
String altitude = "--";
String fixQuality = "--";
String speedKmh = "--";
// Satellite Signal Info
int gpsCount = 0, beidouCount = 0, galileoCount = 0, qzssCount = 0, glonassCount = 0;
String snrList = "";
String nmeaBuffer = "";

void setup() {
 GPSSerial.begin(115200);
 DEBUGSerial.begin(115200);
 DEBUGSerial.println("Waiting for GNSS data...");
}

void loop() {
 readGNSSData();
 static unsigned long lastPrint = 0;
 if (millis() - lastPrint >= PRINT_INTERVAL) {
   lastPrint = millis();
   printGNSSInfo();
   resetCounters();
 }
}

void readGNSSData() {
 while (GPSSerial.available()) {
   char c = GPSSerial.read();
   if (c == '\n') {
     processNMEALine(nmeaBuffer);
     nmeaBuffer = "";
   } else if (c != '\r') {
     nmeaBuffer += c;
   }
 }
}

void processNMEALine(const String &line) {
 if (!line.startsWith("$")) return;
 if (line.startsWith("$GPGSV") || line.startsWith("$GBGSV") ||
     line.startsWith("$GAGSV") || line.startsWith("$GQGSV") ||
     line.startsWith("$GLGSV")) {
   parseGSVLine(line);
 } else if (line.startsWith("$GNRMC")) {
   parseRMC(line);
 } else if (line.startsWith("$GNGGA")) {
   parseGGA(line);
 }
}

void parseRMC(const String &line) {
 int commas[13], idx = -1;
 for (int i = 0; i < 13; i++) {
   idx = line.indexOf(',', idx + 1);
   if (idx == -1) break;
   commas[i] = idx;
 }
 if (commas[1] - commas[0] > 1) {
   String rawTime = line.substring(commas[0] + 1, commas[1]);
   int hour = rawTime.substring(0, 2).toInt();
   int minute = rawTime.substring(2, 4).toInt();
   int second = rawTime.substring(4, 6).toInt();
   utcTime = formatTime(hour, minute, second);
   // Local time adjustment (+5:30)
   minute += 30;
   if (minute >= 60) {
     minute -= 60;
     hour += 1;
   }
   hour = (hour + 5) % 24;
   localTime = formatTime(hour, minute, second);
 }
 if (commas[7] > commas[6]) {
   float knots = line.substring(commas[6] + 1, commas[7]).toFloat();
   speedKmh = String(knots * 1.852, 1);
 }
}

void parseGGA(const String &line) {
 int commas[15], idx = -1;
 for (int i = 0; i < 15; i++) {
   idx = line.indexOf(',', idx + 1);
   if (idx == -1) break;
   commas[i] = idx;
 }
 String latVal = line.substring(commas[1] + 1, commas[2]);
 String latDir = line.substring(commas[2] + 1, commas[3]);
 String lonVal = line.substring(commas[3] + 1, commas[4]);
 String lonDir = line.substring(commas[4] + 1, commas[5]);
 latitude = convertLatLon(latVal, latDir);
 longitude = convertLatLon(lonVal, lonDir);
 fixQuality = line.substring(commas[5] + 1, commas[6]);
 altitude = line.substring(commas[8] + 1, commas[9]) + " m";
}

String convertLatLon(const String &val, const String &dir) {
 if (val.length() < 4) return "--";
 int degLen = (dir == "N" || dir == "S") ? 2 : 3;
 float degrees = val.substring(0, degLen).toFloat();
 float minutes = val.substring(degLen).toFloat();
 float decimal = degrees + (minutes / 60.0);
 if (dir == "S" || dir == "W") decimal *= -1;
 return String(decimal, 6);
}

String formatTime(int h, int m, int s) {
 char buffer[9];
 sprintf(buffer, "%02d:%02d:%02d", h, m, s);
 return String(buffer);
}
String describeFixQuality(const String &code) {
 if (code == "0") return "0 → Not fixed";
 if (code == "1") return "1 → Standalone";
 if (code == "2") return "2 → DGPS Fix";
 if (code == "3") return "3 → PPS Fix";
 if (code == "4") return "4 → RTK Fixed";
 if (code == "5") return "5 → RTK Float";
 return code + " → Unknown";
}

void parseGSVLine(const String &line) {
 if (line.startsWith("$GPGSV")) gpsCount += countSatellitesInLine(line);
 else if (line.startsWith("$GBGSV")) beidouCount += countSatellitesInLine(line);
 else if (line.startsWith("$GAGSV")) galileoCount += countSatellitesInLine(line);
 else if (line.startsWith("$GQGSV")) qzssCount += countSatellitesInLine(line);
 else if (line.startsWith("$GLGSV")) glonassCount += countSatellitesInLine(line);
 int fieldStart = 0, fieldEnd = 0, fieldCount = 0;
 while ((fieldEnd = line.indexOf(',', fieldStart)) != -1) {
   String field = line.substring(fieldStart, fieldEnd);
   fieldStart = fieldEnd + 1;
   fieldCount++;
   if (fieldCount >= 7 && ((fieldCount - 7) % 4 == 0)) {
     appendSNR(field);
   }
 }
 fieldEnd = line.indexOf('*');
 if (fieldEnd != -1 && fieldStart < fieldEnd) {
   appendSNR(line.substring(fieldStart, fieldEnd));
 }
}

int countSatellitesInLine(const String &line) {
 int count = 0, idx = -1;
 for (int i = 0; i < 20; i++) {
   idx = line.indexOf(',', idx + 1);
   if (idx == -1) break;
   if (i >= 4 && (i - 4) % 4 == 0) count++;
 }
 return count;
}
void appendSNR(const String &field) {
 if (field.length() > 0 && isDigit(field[0])) {
   int snr = field.toInt();
   if (snr > 0 && snr <= 99) {
     snrList += String(snr) + " dB  ";
   }
 }
}

void summarizeSNR() {
 int excellent = 0, good = 0, fair = 0, weak = 0, invalid = 0;
 int start = 0;
 while (start >= 0 && start < snrList.length()) {
   int end = snrList.indexOf(" dB", start);
   if (end == -1) break;
   int val = snrList.substring(start, end).toInt();
   if (val >= 40) excellent++;
   else if (val >= 30) good++;
   else if (val >= 20) fair++;
   else if (val >= 1) weak++;
   else invalid++;
   start = snrList.indexOf("  ", end);
   if (start == -1) break;
   start += 2;
 }
 DEBUGSerial.println("---- Signal Strength Summary ----");
 DEBUGSerial.print("Excellent (≥40 dB) : "); DEBUGSerial.println(excellent);
 DEBUGSerial.print("Good     (30–39 dB): "); DEBUGSerial.println(good);
 DEBUGSerial.print("Fair     (20–29 dB): "); DEBUGSerial.println(fair);
 DEBUGSerial.print("Weak     (1–19 dB) : "); DEBUGSerial.println(weak);
 DEBUGSerial.print("Invalid (0 or N/A) : "); DEBUGSerial.println(invalid);
}

void printGNSSInfo() {
 DEBUGSerial.println("\n====== GNSS INFO ======");
 DEBUGSerial.print("Fix Quality: "); DEBUGSerial.println(describeFixQuality(fixQuality));
 if (fixQuality != "0" && fixQuality != "") {
   DEBUGSerial.print("UTC Time   : "); DEBUGSerial.println(utcTime);
   DEBUGSerial.print("Local Time : "); DEBUGSerial.println(localTime);
   DEBUGSerial.print("Latitude   : "); DEBUGSerial.println(latitude);
   DEBUGSerial.print("Longitude  : "); DEBUGSerial.println(longitude);
   DEBUGSerial.print("Speed      : "); DEBUGSerial.print(speedKmh); DEBUGSerial.println(" km/h");
   DEBUGSerial.print("Altitude   : "); DEBUGSerial.println(altitude);
 } else {
   DEBUGSerial.println("UTC Time   : --");
   DEBUGSerial.println("Local Time : --");
   DEBUGSerial.println("Latitude   : --");
   DEBUGSerial.println("Longitude  : --");
   DEBUGSerial.println("Speed      : --");
   DEBUGSerial.println("Altitude   : --");
 }
 DEBUGSerial.println("---- Satellites Visible ----");
 DEBUGSerial.print("GPS(USA)        : "); DEBUGSerial.println(gpsCount);
 DEBUGSerial.print("BeiDou(China)   : "); DEBUGSerial.println(beidouCount);
 DEBUGSerial.print("Galileo(Europe) : "); DEBUGSerial.println(galileoCount);
 DEBUGSerial.print("QZSS(Japan)     : "); DEBUGSerial.println(qzssCount);
 DEBUGSerial.print("GLONASS(Russia) : "); DEBUGSerial.println(glonassCount);
 summarizeSNR();
 DEBUGSerial.println("===================================");
}

void resetCounters() {
 gpsCount = beidouCount = galileoCount = qzssCount = glonassCount = 0;
 snrList = "";
}

Projets liés aux modules GNSS

#define GPSSerial  Serial
#define DEBUGSerial Serial
void setup()  
{
 GPSSerial.begin(115200);      
 DEBUGSerial.begin(115200);  
 DEBUGSerial.println("Waiting for GNSS data...");
}
void loop()  
{
 while (GPSSerial.available()) {  
    DEBUGSerial.write(GPSSerial.read());
 }
}

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