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Diffstat (limited to 'Transceiver52M/radioInterfaceDiversity.cpp')
| -rw-r--r-- | Transceiver52M/radioInterfaceDiversity.cpp | 243 |
1 files changed, 0 insertions, 243 deletions
diff --git a/Transceiver52M/radioInterfaceDiversity.cpp b/Transceiver52M/radioInterfaceDiversity.cpp deleted file mode 100644 index c78310c..0000000 --- a/Transceiver52M/radioInterfaceDiversity.cpp +++ /dev/null @@ -1,243 +0,0 @@ -/* - * SSE Convolution - * Copyright (C) 2013 Thomas Tsou <tom@tsou.cc> - * - * This library is free software; you can redistribute it and/or - * modify it under the terms of the GNU Lesser General Public - * License as published by the Free Software Foundation; either - * version 2.1 of the License, or (at your option) any later version. - * - * This library is distributed in the hope that it will be useful, - * but WITHOUT ANY WARRANTY; without even the implied warranty of - * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU - * Lesser General Public License for more details. - * - * You should have received a copy of the GNU Lesser General Public - * License along with this library; if not, write to the Free Software - * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA - */ - -#include <radioInterface.h> -#include <Logger.h> - -#include "Resampler.h" - -extern "C" { -#include "convert.h" -} - -/* Resampling parameters for 64 MHz clocking */ -#define RESAMP_64M_INRATE 20 -#define RESAMP_64M_OUTRATE 80 - -/* Downlink block size */ -#define CHUNK 625 - -/* Universal resampling parameters */ -#define NUMCHUNKS 48 - -/* - * Resampling filter bandwidth scaling factor - * This narrows the filter cutoff relative to the output bandwidth - * of the polyphase resampler. At 4 samples-per-symbol using the - * 2 pulse Laurent GMSK approximation gives us below 0.5 degrees - * RMS phase error at the resampler output. - */ -#define RESAMP_TX4_FILTER 0.45 - -static size_t resamp_inrate = 0; -static size_t resamp_inchunk = 0; -static size_t resamp_outrate = 0; -static size_t resamp_outchunk = 0; - -RadioInterfaceDiversity::RadioInterfaceDiversity(RadioDevice *wRadio, - size_t tx_sps, size_t chans) - : RadioInterface(wRadio, tx_sps, 1, chans, 2), outerRecvBuffer(NULL), - mDiversity(false), mFreqSpacing(0.0) -{ -} - -RadioInterfaceDiversity::~RadioInterfaceDiversity() -{ - close(); -} - -void RadioInterfaceDiversity::close() -{ - delete outerRecvBuffer; - delete dnsampler; - - dnsampler = NULL; - outerRecvBuffer = NULL; - - if (recvBuffer.size()) - recvBuffer[0] = NULL; - - RadioInterface::close(); -} - -bool RadioInterfaceDiversity::setupDiversityChannels() -{ - size_t inner_rx_len; - - /* Inner and outer rates */ - resamp_inrate = RESAMP_64M_INRATE; - resamp_outrate = RESAMP_64M_OUTRATE; - resamp_inchunk = resamp_inrate * 4; - resamp_outchunk = resamp_outrate * 4; - - /* Buffer lengths */ - inner_rx_len = NUMCHUNKS * resamp_inchunk; - - /* Inside buffer must hold at least 2 bursts */ - if (inner_rx_len < 157 * mSPSRx * 2) { - LOG(ALERT) << "Invalid inner buffer size " << inner_rx_len; - return false; - } - - dnsampler = new Resampler(resamp_inrate, resamp_outrate); - if (!dnsampler->init()) { - LOG(ALERT) << "Rx resampler failed to initialize"; - return false; - } - - /* One Receive buffer and downsampler per diversity channel */ - for (size_t i = 0; i < mMIMO * mChans; i++) { - recvBuffer[i] = new RadioBuffer(NUMCHUNKS, - resamp_inchunk, 0, false); - } - - return true; -} - -/* Initialize I/O specific objects */ -bool RadioInterfaceDiversity::init(int type) -{ - int outer_rx_len; - - if ((mMIMO != 2) || (mChans != 2)) { - LOG(ALERT) << "Unsupported channel configuration " << mChans; - return false; - } - - /* Resize for channel combination */ - sendBuffer.resize(mChans); - recvBuffer.resize(mChans * mMIMO); - convertSendBuffer.resize(mChans); - convertRecvBuffer.resize(mChans); - mReceiveFIFO.resize(mChans); - phases.resize(mChans); - - if (!setupDiversityChannels()) - return false; - - outer_rx_len = resamp_outchunk; - - for (size_t i = 0; i < mChans; i++) { - /* Full rate float and integer outer receive buffers */ - convertRecvBuffer[i] = new short[outer_rx_len * 2]; - - /* Send buffers (not-resampled) */ - sendBuffer[i] = new RadioBuffer(NUMCHUNKS, CHUNK * mSPSTx, 0, true); - convertSendBuffer[i] = new short[CHUNK * mSPSTx * 2]; - } - - outerRecvBuffer = new signalVector(outer_rx_len, dnsampler->len()); - - return true; -} - -bool RadioInterfaceDiversity::tuneRx(double freq, size_t chan) -{ - double f0, f1; - - if (chan > 1) - return false; - - if (!mRadio->setRxFreq(freq, chan)) - return false; - - f0 = mRadio->getRxFreq(0); - f1 = mRadio->getRxFreq(1); - - mFreqSpacing = f1 - f0; - - if (abs(mFreqSpacing) <= 600e3) - mDiversity = true; - else - mDiversity = false; - - return true; -} - -/* Receive a timestamped chunk from the device */ -void RadioInterfaceDiversity::pullBuffer() -{ - bool local_underrun; - int rc, num, path0, path1; - signalVector *shift, *base; - float *in, *out, rate = -mFreqSpacing * 2.0 * M_PI / 1.08333333e6; - - if (recvBuffer[0]->getFreeSegments() <= 0) - return; - - /* Outer buffer access size is fixed */ - num = mRadio->readSamples(convertRecvBuffer, - resamp_outchunk, - &overrun, - readTimestamp, - &local_underrun); - if ((size_t) num != resamp_outchunk) { - LOG(ALERT) << "Receive error " << num; - return; - } - - for (size_t i = 0; i < mChans; i++) { - convert_short_float((float *) outerRecvBuffer->begin(), - convertRecvBuffer[i], 2 * resamp_outchunk); - - if (!i) { - path0 = 0; - path1 = 2; - } else { - path0 = 3; - path1 = 1; - } - - /* Diversity path 1 */ - base = outerRecvBuffer; - in = (float *) base->begin(); - out = (float *) recvBuffer[path0]->getWriteSegment(); - - rc = dnsampler->rotate(in, resamp_outchunk, - out, resamp_inchunk); - if (rc < 0) { - LOG(ALERT) << "Sample rate downsampling error"; - } - - /* Enable path 2 if Nyquist bandwidth is sufficient */ - if (!mDiversity) - continue; - - /* Diversity path 2 */ - shift = new signalVector(base->size(), base->getStart()); - in = (float *) shift->begin(); - out = (float *) recvBuffer[path1]->getWriteSegment(); - - rate = i ? -rate : rate; - if (!frequencyShift(shift, base, rate, phases[i], &phases[i])) { - LOG(ALERT) << "Frequency shift failed"; - } - - rc = dnsampler->rotate(in, resamp_outchunk, - out, resamp_inchunk); - if (rc < 0) { - LOG(ALERT) << "Sample rate downsampling error"; - } - - delete shift; - } - - underrun |= local_underrun; - readTimestamp += (TIMESTAMP) resamp_outchunk; -} |