/*
* ToneDetect3.ino Test the CTCSS tone detection
* using the OpenAudio_ArduinoLibrary analyze_CTCSS_F32 class.
* This is also an example of generating and detecting radio
* narrow-band frequency modulation (NBFM. This covers the case where the
* FM deviation is in the same order as the modulation frequencies.
* CTCSS sub-audible tones (see Wikipedia) are widely used to
* allow stations to only hear the desired transmitters. The frequencies
* are all lower than that of voice to allow separation by filtering.
*
* Bob Larkin 26 March 2021
* Revised 22 Jan 2022.
* Public Domain
*/
#include "AudioStream_F32.h"
#include "Arduino.h"
#include "Audio.h"
#include "OpenAudio_ArduinoLibrary.h"
// #define OUTPUT_QUEUE
// T3.x supported sample rates: 2000, 8000, 11025, 16000, 22050, 24000, 32000, 44100, 44117, 48000,
// 88200, 88235 (44117*2), 95680, 96000, 176400, 176470, 192000
// T4.x supports any sample rate the codec will handle.
// The CTCSS detector supports a restricted st of sample rates (details below).
const float sample_rate_Hz = 44117.0f;
const int audio_block_samples = 128; // Use this - only one supported in CTCSS detector
AudioSettings_F32 audio_settings(sample_rate_Hz, audio_block_samples); // Not used, all at default
const float CTCSSFreq = 103.500f;
/* FIR filter designed with http://t-filter.appspot.com
* This seems to be a good I-F filter for 5 kHz deviation NBFM.
* Sampling frequency: 44100 Hz
* 0 Hz - 6300 Hz, att >-62.1 dB
* 8000 Hz - 20000 Hz Ripple = 0.06 dB
* 21700 Hz - 22050 Hz att >-62.1 dB
*/
float firFM_BPF[82] = { // Limit noise going to FM detector
0.0000000000000000000,
0.00008365261860118879,
0.0006583187950336784,
-0.0019407568703118934,
-0.00009987233532798062,
0.00032719088373367114,
0.0015310693898116902,
0.000955022003263755,
-0.0014168349573391522,
-0.0012792163039246237,
-0.0028041109113356045,
0.003423773414325396,
0.0005879630239341677,
0.005484189218478419,
-0.005929117878887913,
-0.00011592770526681765,
-0.008306219532671027,
0.007927691595232189,
0.0011012110020438936,
0.010098403965529463,
-0.008003622491352998,
-0.0051152410852304386,
-0.00960701825591872,
0.004774918283483265,
0.013581334230222949,
0.006115374322484461,
0.0025168498118005173,
-0.02728352305492423,
-0.00013301923349161136,
-0.013504140226622814,
0.04621408618779683,
-0.005938008431812001,
0.026530407240648667,
-0.0703999968346119,
0.006639153066796368,
-0.038963325061155324,
0.10421524449162319,
0.01319721488745073,
0.04792495681421007,
-0.19558525086465353,
-0.21559102765412194,
0.6154759104918608,
-0.21559102765412194,
-0.19558525086465353,
0.04792495681421007,
0.01319721488745073,
0.10421524449162319,
-0.038963325061155324,
0.006639153066796368,
-0.0703999968346119,
0.026530407240648667,
-0.005938008431812001,
0.04621408618779683,
-0.013504140226622814,
-0.00013301923349161136,
-0.02728352305492423,
0.0025168498118005173,
0.006115374322484461,
0.013581334230222949,
0.004774918283483265,
-0.00960701825591872,
-0.0051152410852304386,
-0.008003622491352998,
0.010098403965529463,
0.0011012110020438936,
0.007927691595232189,
-0.008306219532671027,
-0.00011592770526681765,
-0.005929117878887913,
0.005484189218478419,
0.0005879630239341677,
0.003423773414325396,
-0.0028041109113356045,
-0.0012792163039246237,
-0.0014168349573391522,
0.000955022003263755,
0.0015310693898116902,
0.00032719088373367114,
-0.00009987233532798062,
-0.0019407568703118934,
0.0006583187950336784,
0.00008365261860118879};
// Transmitter:
// Use SineCosine_F32 as it allows amplitudes greater than
// 1.0 (this is FP and that is OK). Use sine channnel only.
AudioSynthSineCosine_F32 sine1; //xy=62,181
AudioSynthGaussian_F32 noiseWhite1; //xy=68.5,265
AudioSynthGaussian_F32 noiseWhite2; //xy=68.5,379
AudioAnalyzeRMS_F32 rms2; //xy=103,314
AudioFilterBiquad_F32 biQuad1; //xy=223,265
AudioMixer4_F32 mixer4_1; //xy=229,195
AudioMixer4_F32 mixer4_2; //xy=236,381
RadioFMDetector_F32 FMDetector1; //xy=258,476
AudioFilterFIR_F32 fir1; //xy=365,381
radioModulatedGenerator_F32 modulator1; //xy=395,189
AudioAnalyzeRMS_F32 rms1; //xy=426,125
analyze_CTCSS_F32 toneDet1; //xy=200,400
// AudioRecordQueue_F32 recordQueue1; //xy=446,446
AudioOutputI2S_F32 audioOutI2S1; //xy=448,489
AudioConnection_F32 patchCord1(sine1, 0, mixer4_1, 0);
AudioConnection_F32 patchCord2(noiseWhite1, biQuad1);
AudioConnection_F32 patchCord3(noiseWhite2, 0, mixer4_2, 1);
AudioConnection_F32 patchCord4(fir1, rms2); // patchCord4(noiseWhite2, rms2);
AudioConnection_F32 patchCord5(biQuad1, 0, mixer4_1, 1);
AudioConnection_F32 patchCord6(mixer4_1, 0, modulator1, 1);
AudioConnection_F32 patchCord7(mixer4_2, fir1);
AudioConnection_F32 patchCord8(FMDetector1, 0, audioOutI2S1, 0);
AudioConnection_F32 patchCord9(FMDetector1, 0, audioOutI2S1, 1);
AudioConnection_F32 patchCordA(FMDetector1, 0, toneDet1, 0);
// AudioConnection_F32 patchCord10(FMDetector1, 0, recordQueue1, 0);
AudioConnection_F32 patchCord11(fir1, FMDetector1);
AudioConnection_F32 patchCord12(modulator1, 0, mixer4_2, 0);
AudioConnection_F32 patchCord13(modulator1, 0, rms1, 0);
AudioControlSGTL5000 sgtl5000_1; //xy=157,796
// #define SAMPLE_RATE 44117.0f
// #define DETECTOR_TIME 300.0f
// #define NWINDOW (uint16_t)( 0.5 + SAMPLE_RATE * DETECTOR_TIME / 32000.0f )
void setup() {
Serial.begin(300); // Any value
delay(1000);
Serial.println("OpenAudio_ArduinoLibrary - Full FM Test CTCSS Tone Detector");
// AudioMemory(5);
AudioMemory_F32(50, audio_settings);
sgtl5000_1.enable();
// NBFM Transmitter:
sine1.frequency(CTCSSFreq);
sine1.amplitude(0.75f); // CTCSS tone 750 Hz deviation (15% of 5000)
noiseWhite1.amplitude(2.0f); // RMS 2000 Hz deviation, 1 sigma
modulator1.setFMScale(1000.0f); // Sine wave ampl=1.0 is now 1 kHz dev
// Bandpass the noise a bit to make it imitate voice, grossly!
biQuad1.setBandpass(0, 800.0f, 4.0f); // (uint32_t stage, float frequency, float q)
biQuad1.begin();
// (_doAM, _doPM, _doFM, _bothIQ)
modulator1.doModulation_AM_PM_FM(false, false, true, false);
modulator1.frequency(15000.0f); // Carrier frequency
modulator1.amplitude(0.01f); // Set in loop below
// NBFM Receiver:
noiseWhite2.amplitude(0.01f); // Receiver noise arbitrary level here
fir1.begin(firFM_BPF, 82, 128); // NBFM I-F filter
// The FM detector has error checking during object construction
// when Serial.print is not available. See RadioFMDetector_F32.h:
Serial.print("FM Initialization errors: ");
Serial.println( FMDetector1.returnInitializeFMError() );
// FMDetector1.setSquelchThreshold(0.7f);
FMDetector1.frequency(15000.0f);
// recordQueue1.begin();
// Sub-audible tone detector:
// CTCSS ranges from 67 to 254 Hz
// Actual CTCSS use seems to be 77.0 to 203.5 Hz
toneDet1.initCTCSS();
toneDet1.frequency(CTCSSFreq); // or (CTCSSFreq, 300.0);
toneDet1.thresholds(0.0f, 0.4f);
delay(500);
Serial.println(waitTone2()); // Just to load filters
modulator1.amplitude(0.01);
measureDataPoint();
Serial.print("\nCTCSS Freq = "); Serial.println(CTCSSFreq);
Serial.println("\n pTone pRef pTone/pRef pSigdB pNoisedB S/N dB");
for(float sig=0.00316228; sig<0.158114; sig*=1.04)
{
modulator1.amplitude(sig);
measureDataPoint();
}
}
void loop() {
// measureDataPoint();
}
/*
while (!rms2.available()) ;
float pNoise = 20.0f*log10f(rms2.read());
while (!rms2.available()) ;
pNoise = 20.0f*log10f(rms2.read());
while (!rms2.available()) ;
pNoise = 20.0f*log10f(rms2.read());
Serial.print("FM Det out (dB) = ");
Serial.println(pNoise, 3);
*/
#ifdef OUTPUT_QUEUE
if( recordQueue1.available() )
{ pq = recordQueue1.readBuffer();
for(int i=0; i<128; i++)
Serial.println(*(pq + i),7);
recordQueue1.freeBuffer();
}
#endif
void measureDataPoint(void) {
if(!waitTone2()) {Serial.println("No tone output"); return;}
float pt = toneDet1.readTonePower();
float pr = toneDet1.readRefPower();
Serial.print(pt, 9);
Serial.print(", ");
// Serial.print(10.0f*log10f(toneDet1.readRefPower()), 3);
Serial.print(pr, 9);
Serial.print(", ");
Serial.print(pt/pr, 7);
Serial.print(", ");
while(!rms1.available() || !rms2.available() ) Serial.print(rms2.available() );
float pSig = 20.0f*log10f(rms1.read());
float pNoise = 20.0f*log10f(rms2.read());
Serial.print(pSig, 3);
Serial.print(", ");
Serial.print(pNoise, 3);
Serial.print(", ");
Serial.println(pSig - pNoise, 3);
}
bool waitTone2(void)
{
unsigned long int t;
t=micros();
while(1) {
if(toneDet1.available()) return true;
if( (micros()-t) > 1000000UL) return false;
}
}