// CESSB_ZeroIF.ino // This tests the Controlled Envelope Single Sideband generator version // that produces a zero-IF signal 0to 3kHz or 0 to -3 kHz. // Uses radioCESSB_Z_transmit_F32.h and .cpp. See the .h file for // more information and references. // Tests with voice from SD Card file and a 1 second 750 Hz tone burst. // // The SD card may connect to different pins, depending on the // hardware you are using. Configure the SD card // pins to match your hardware. It is set for T4.x Rev D PJRC // Teensy Audio Adaptor card here. // // Your microSD card must have the WAV file loaded to it: // W9GR48.WAV // These are at // https://github.com/chipaudette/OpenAudio_ArduinoLibrary/blob/master/utility/ // // This example code is in the public domain. #include #include #include #include #include "OpenAudio_ArduinoLibrary.h" // 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. const float sample_rate_Hz = 48000.0f; const int audio_block_samples = 128; // Always 128 AudioSettings_F32 audio_settings(sample_rate_Hz, audio_block_samples); AudioSynthWaveformSine_F32 sine1(audio_settings); AudioSDPlayer_F32 playWav1(audio_settings); AudioMixer4_F32 mixer4_0; radioCESSB_Z_transmit_F32 cessb1(audio_settings); RadioIQMixer_F32 iqMixer1(audio_settings); AudioMixer4_F32 mixer4_2; AudioFilter90Deg_F32 filter90deg1(audio_settings); RadioIQMixer_F32 iqMixer2(audio_settings); AudioMixer4_F32 mixer4_1; AudioOutputI2S_F32 audioOutput(audio_settings); AudioAnalyzeFFT1024_F32 fft1; AudioConnection_F32 patchCord0(playWav1, 0, mixer4_0, 0); AudioConnection_F32 patchCordb(sine1, 0, mixer4_0, 1); AudioConnection_F32 patchCordc(mixer4_0, 0, cessb1, 0); AudioConnection_F32 patchCord1(cessb1, 0, iqMixer1, 0); AudioConnection_F32 patchCord2(cessb1, 1, iqMixer1, 1); AudioConnection_F32 patchCord9(iqMixer1, 0, mixer4_2, 0); AudioConnection_F32 patchCord10(iqMixer1,1, mixer4_2, 1); // mixer4_2 is transmitter SSB output, iqMixer2 is receiver input AudioConnection_F32 patchCord14(mixer4_2,0, iqMixer2, 0); AudioConnection_F32 patchCord3(iqMixer2, 0, filter90deg1, 0); AudioConnection_F32 patchCord4(iqMixer2, 1, filter90deg1, 1); AudioConnection_F32 patchCord7(filter90deg1, 0, mixer4_1, 0); AudioConnection_F32 patchCord8(filter90deg1, 1, mixer4_1, 1); AudioConnection_F32 patchCord11(mixer4_1, 0, audioOutput, 0); AudioConnection_F32 patchCord12(mixer4_1, 0, audioOutput, 1); AudioConnection_F32 patchCord13(mixer4_2, 0, fft1, 0); AudioControlSGTL5000 sgtl5000_1; // Use these with the Teensy 4.x Rev D Audio Shield (NOT for T3.x) #define SDCARD_CS_PIN_Z 10 #define SDCARD_MOSI_PIN_Z 11 #define SDCARD_SCK_PIN_Z 13 // Filter for AudioFilter90Deg_F32 hilbert1, only for receiving the CESSB #include "hilbert251A_Z_.h" // wavData is a global struct, definined in AudioSDPlayer_F32.h // This provides information about the current WAV file to this .INO struct wavData* pCurrentWavData; // And data about the CESSB struct levelsZ* pLevelData; uint32_t writeOne = 0; uint32_t cntFFT = 0; uint32_t ttt; // For timing test audio uint32_t tp; void setup() { // ********** SETUP ********** Serial.begin(9600); delay(1000); Serial.println("*** Test CESSB Zero-IF from SD Card Voice Sample ***"); AudioMemory_F32(70, audio_settings); pCurrentWavData = playWav1.getCurrentWavData(); sgtl5000_1.enable(); delay(500); SPI.setMOSI(SDCARD_MOSI_PIN_Z); SPI.setSCK(SDCARD_SCK_PIN_Z); Serial.print("SD.begin() returns "); Serial.println(SD.begin(SDCARD_CS_PIN_Z)); // sine0.frequency(468.75f); // 2-tone generators // sine0.amplitude(0.707107); sine1.frequency(750.0f); sine1.amplitude(0.707107); // Build the CESSB SSB transmitter // The WAV file has carefully controlled 0.707 peaks. We bring these to 1.000 mixer4_0.gain(0, 1.41421356f); // Play WAV file on mixer4_0.gain(2, 0.0); // Sine Wave 1 off cessb1.setSampleRate_Hz(48000.0f); // Set input, correction, and output gains float32_t Pre_CESSB_Gain = 1.5f; // Use to set amount of clipping, 1.0 to 2.0f, 3 is excessive cessb1.setGains(Pre_CESSB_Gain, 1.4f, 1.0f); cessb1.setSideband(false); pLevelData = cessb1.getLevels(0); // Gets pointer to struct // Generate SSB at 15 kHz from zero-IF signal of CESSB generator iqMixer1.useTwoChannel(true); iqMixer1.frequency(15000); mixer4_2.gain(1, 1.0f); // 1.0f for LSB, -1.0f for USB // Need a receiver for the SSB transmitter to let us hear the results. iqMixer2.frequency(15000.0f); iqMixer2.useTwoChannel(false); filter90deg1.begin(hilbert251A, 251); mixer4_1.gain(0, -1.0f); // LSB, + for USB audioOutput.setGain(0.02); // <<< Output volume control fft1.setOutputType(FFT_DBFS); fft1.windowFunction(AudioWindowBlackmanHarris1024); fft1.setNAverage(16); ttt = millis(); // Time test audio tp=millis(); } void playFile(const char *filename) { if(playWav1.isPlaying()) return; Serial.println(""); Serial.print("Playing file: "); Serial.println(filename); playWav1.play(filename); // Start playing the file. // A brief delay for the library read WAV info delay(25); Serial.print("WAV file format = "); Serial.println(pCurrentWavData->audio_format); Serial.print("WAV number channels = "); Serial.println(pCurrentWavData->num_channels); Serial.print("WAV File Sample Rate = "); Serial.println(pCurrentWavData->sample_rate); Serial.print("Number of bits per Sample = "); Serial.println(pCurrentWavData->bits); Serial.print("File length, seconds = "); Serial.println(0.001f*(float32_t)playWav1.lengthMillis(), 3); } void loop() { uint32_t tt=millis() - ttt; if(tt < 2000) { // Thanks to W9GR for the test file, W9GR48.WAV. This is intended for testing // the CESSB radio transmission system. playFile("W9GR48.WAV"); mixer4_0.gain(0, 1.41421356f); // Play WAV file on mixer4_0.gain(1, 0.0f); // Sine Wave 1 off } else if(tt > 12300 && tt<13300) { mixer4_0.gain(1, 0.0f); // Play WAV file off // The following puts a 1-sec 750 Hz, full amplitude tone into the input // .707 on the generator and 1.414 here make the peak sine wave 1.000 at the CESSB input mixer4_0.gain(1, 1.41421356f); // Sine Wave 1 on, 750 Hz } else if(tt >= 13300) { mixer4_0.gain(0, 1.41421356f); // Play WAV file on mixer4_0.gain(1, 0.0f); // Sine Wave 1 off ttt = millis(); // Start again } delay(1); // Un-comment the following to print out the spectrum /* if(fft1.available() && ++cntFFT>100 && cntFFT<102) { for(int kk=0; kk<512; kk++) { Serial.print(46.875f*(float32_t)kk); Serial.print(","); Serial.println(fft1.read(kk)); } } */ if(cessb1.levelDataCount() > 300) // Typically 300 to 3000 { cessb1.getLevels(1); // Cause write of data to struct & reset // Detailed Report Serial.print(10.0f*log10f(pLevelData->pwr0)); Serial.print(" In Ave Pwr Out "); Serial.println(10.0f*log10f(pLevelData->pwr1)); Serial.print(20.0f*log10f(pLevelData->peak0)); Serial.print(" In Peak Out "); Serial.println(20.0f*log10f(pLevelData->peak1)); Serial.print(pLevelData->peak0, 6); Serial.print(" In Peak Volts Out "); Serial.println(pLevelData->peak1, 6); Serial.print("Enhancement = "); float32_t enhance = (10.0f*log10f(pLevelData->pwr1) - 20.0f*log10f(pLevelData->peak1)) - (10.0f*log10f(pLevelData->pwr0) - 20.0f*log10f(pLevelData->peak0)); if(enhance<1.0f) enhance = 1.0f; Serial.print(enhance); Serial.println(" dB"); /* // CSV Report suitable for entering to spread sheet // InAve, InPk, OutAve, OutPk, EnhancementdB Serial.print(pLevelData->pwr0, 5); Serial.print(","); Serial.print(pLevelData->peak0, 5); Serial.print(","); Serial.print(pLevelData->pwr1, 5); Serial.print(","); Serial.print(pLevelData->peak1, 5); Serial.print(","); float32_t enhance = (10.0f*log10f(pLevelData->pwr1) - 20.0f*log10f(pLevelData->peak1)) - (10.0f*log10f(pLevelData->pwr0) - 20.0f*log10f(pLevelData->peak0)); if(enhance<1.0f) enhance = 1.0f; Serial.println(enhance); */ } }