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Fix channel gap on upper edge of spectrum

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This commit is contained in:
Charles J. Cliffe 2015-10-17 18:25:14 -04:00
parent f1475fb9be
commit 6ee51711db
1 changed files with 15 additions and 6 deletions
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21
src/sdr/SDRPostThread.cpp
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@ -63,8 +63,8 @@ void SDRPostThread::initPFBChannelizer() {
chanBw = (sampleRate / numChannels); chanBw = (sampleRate / numChannels);
chanCenters.resize(numChannels); chanCenters.resize(numChannels+1);
demodChannelActive.resize(numChannels); demodChannelActive.resize(numChannels+1);
// std::cout << "Channel bandwidth spacing: " << (chanBw) << std::endl; // std::cout << "Channel bandwidth spacing: " << (chanBw) << std::endl;
} }
@ -125,6 +125,7 @@ void SDRPostThread::updateChannels() {
chanCenters[i] = frequency + ofs; chanCenters[i] = frequency + ofs;
chanCenters[i+(numChannels/2)] = frequency - (sampleRate/2) + ofs; chanCenters[i+(numChannels/2)] = frequency - (sampleRate/2) + ofs;
} }
chanCenters[numChannels] = frequency + (sampleRate/2);
} }
void SDRPostThread::run() { void SDRPostThread::run() {
@ -238,7 +239,7 @@ void SDRPostThread::run() {
for (int i = 0; i < nRunDemods; i++) { for (int i = 0; i < nRunDemods; i++) {
DemodulatorInstance *demod = runDemods[i]; DemodulatorInstance *demod = runDemods[i];
long long minDelta = data_in->sampleRate; long long minDelta = data_in->sampleRate;
for (int j = 0, jMax = numChannels; j < jMax; j++) { for (int j = 0, jMax = numChannels+1; j < jMax; j++) {
// Distance from channel center to demod center // Distance from channel center to demod center
long long fdelta = abs(demod->getFrequency() - chanCenters[j]); long long fdelta = abs(demod->getFrequency() - chanCenters[j]);
if (fdelta < minDelta) { if (fdelta < minDelta) {
@ -259,7 +260,7 @@ void SDRPostThread::run() {
} }
// Run channels // Run channels
for (int i = 0; i < numChannels; i++) { for (int i = 0; i < numChannels+1; i++) {
bool doVis = (activeDemodChannel == i) && (iqActiveDemodVisualQueue != NULL) && !iqActiveDemodVisualQueue->full(); bool doVis = (activeDemodChannel == i) && (iqActiveDemodVisualQueue != NULL) && !iqActiveDemodVisualQueue->full();
DemodulatorThreadIQData *demodDataOut = buffers.getBuffer(); DemodulatorThreadIQData *demodDataOut = buffers.getBuffer();
@ -277,18 +278,26 @@ void SDRPostThread::run() {
demodDataOut->data.resize(chanDataSize); demodDataOut->data.resize(chanDataSize);
} }
int idx = i;
// Extra channel wraps lower side band of lowest channel
// to fix frequency gap on upper side of spectrum
if (i == numChannels) {
idx = (numChannels/2);
}
// prepare channel data buffer // prepare channel data buffer
if (i == 0) { // Channel 0 requires DC correction if (i == 0) { // Channel 0 requires DC correction
if (dcBuf.size() != chanDataSize) { if (dcBuf.size() != chanDataSize) {
dcBuf.resize(chanDataSize); dcBuf.resize(chanDataSize);
} }
for (int j = 0, idx = i; j < chanDataSize; j++) { for (int j = 0; j < chanDataSize; j++) {
idx += numChannels; idx += numChannels;
dcBuf[j] = dataOut[idx]; dcBuf[j] = dataOut[idx];
} }
iirfilt_crcf_execute_block(dcFilter, &dcBuf[0], chanDataSize, &demodDataOut->data[0]); iirfilt_crcf_execute_block(dcFilter, &dcBuf[0], chanDataSize, &demodDataOut->data[0]);
} else { } else {
for (int j = 0, idx = i; j < chanDataSize; j++) { for (int j = 0; j < chanDataSize; j++) {
idx += numChannels; idx += numChannels;
demodDataOut->data[j] = dataOut[idx]; demodDataOut->data[j] = dataOut[idx];
} }