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Diffstat (limited to 'src/OfdmGenerator.cpp')
| -rw-r--r-- | src/OfdmGenerator.cpp | 195 |
1 files changed, 195 insertions, 0 deletions
diff --git a/src/OfdmGenerator.cpp b/src/OfdmGenerator.cpp new file mode 100644 index 0000000..d87d68a --- /dev/null +++ b/src/OfdmGenerator.cpp @@ -0,0 +1,195 @@ +/* + Copyright (C) 2005, 2006, 2007, 2008, 2009, 2010, 2011 Her Majesty + the Queen in Right of Canada (Communications Research Center Canada) + */ +/* + This file is part of CRC-DADMOD. + + CRC-DADMOD is free software: you can redistribute it and/or modify + it under the terms of the GNU General Public License as + published by the Free Software Foundation, either version 3 of the + License, or (at your option) any later version. + + CRC-DADMOD 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 General Public License for more details. + + You should have received a copy of the GNU General Public License + along with CRC-DADMOD. If not, see <http://www.gnu.org/licenses/>. + */ + +#include "OfdmGenerator.h" +#include "PcDebug.h" +#include "kiss_fftsimd.h" + +#include <stdio.h> +#include <stdexcept> +#include <assert.h> +#include <complex> +typedef std::complex<float> complexf; + + +OfdmGenerator::OfdmGenerator(size_t nbSymbols, + size_t nbCarriers, + size_t spacing, + bool inverse) : + ModCodec(ModFormat(myNbSymbols * myNbCarriers * sizeof(FFT_TYPE)), + ModFormat(myNbSymbols * mySpacing * sizeof(FFT_TYPE))), + myFftPlan(NULL), + myFftBuffer(NULL), + myNbSymbols(nbSymbols), + myNbCarriers(nbCarriers), + mySpacing(spacing) +{ + PDEBUG("OfdmGenerator::OfdmGenerator(%zu, %zu, %zu, %s) @ %p\n", + nbSymbols, nbCarriers, spacing, inverse ? "true" : "false", this); + + if (nbCarriers > spacing) { + throw std::runtime_error( + "OfdmGenerator::OfdmGenerator nbCarriers > spacing!"); + } + + if (inverse) { + myPosDst = (nbCarriers & 1 ? 0 : 1); + myPosSrc = 0; + myPosSize = (nbCarriers + 1) / 2; + myNegDst = spacing - (nbCarriers / 2); + myNegSrc = (nbCarriers + 1) / 2; + myNegSize = nbCarriers / 2; + } else { + myPosDst = (nbCarriers & 1 ? 0 : 1); + myPosSrc = nbCarriers / 2; + myPosSize = (nbCarriers + 1) / 2; + myNegDst = spacing - (nbCarriers / 2); + myNegSrc = 0; + myNegSize = nbCarriers / 2; + } + myZeroDst = myPosDst + myPosSize; + myZeroSize = myNegDst - myZeroDst; + + PDEBUG(" myPosDst: %u\n", myPosDst); + PDEBUG(" myPosSrc: %u\n", myPosSrc); + PDEBUG(" myPosSize: %u\n", myPosSize); + PDEBUG(" myNegDst: %u\n", myNegDst); + PDEBUG(" myNegSrc: %u\n", myNegSrc); + PDEBUG(" myNegSize: %u\n", myNegSize); + PDEBUG(" myZeroDst: %u\n", myZeroDst); + PDEBUG(" myZeroSize: %u\n", myZeroSize); + + myFftPlan = kiss_fft_alloc(mySpacing, 1, NULL, NULL); + myFftBuffer = (FFT_TYPE*)memalign(16, mySpacing * sizeof(FFT_TYPE)); +} + + +OfdmGenerator::~OfdmGenerator() +{ + PDEBUG("OfdmGenerator::~OfdmGenerator() @ %p\n", this); + + if (myFftPlan != NULL) { + kiss_fft_free(myFftPlan); + } + if (myFftBuffer != NULL) { + free(myFftBuffer); + } + kiss_fft_cleanup(); +} + + +int OfdmGenerator::process(Buffer* const dataIn, Buffer* dataOut) +{ + PDEBUG("OfdmGenerator::process(dataIn: %p, dataOut: %p)\n", + dataIn, dataOut); + + dataOut->setLength(myNbSymbols * mySpacing * sizeof(complexf)); + + FFT_TYPE* in = reinterpret_cast<FFT_TYPE*>(dataIn->getData()); + FFT_TYPE* out = reinterpret_cast<FFT_TYPE*>(dataOut->getData()); + size_t sizeIn = dataIn->getLength() / sizeof(complexf); + size_t sizeOut = dataOut->getLength() / sizeof(complexf); + + if (sizeIn != myNbSymbols * myNbCarriers) { + PDEBUG("Nb symbols: %zu\n", myNbSymbols); + PDEBUG("Nb carriers: %zu\n", myNbCarriers); + PDEBUG("Spacing: %zu\n", mySpacing); + PDEBUG("\n%zu != %zu\n", sizeIn, myNbSymbols * myNbCarriers); + throw std::runtime_error( + "OfdmGenerator::process input size not valid!"); + } + if (sizeOut != myNbSymbols * mySpacing) { + PDEBUG("Nb symbols: %zu\n", myNbSymbols); + PDEBUG("Nb carriers: %zu\n", myNbCarriers); + PDEBUG("Spacing: %zu\n", mySpacing); + PDEBUG("\n%zu != %zu\n", sizeIn, myNbSymbols * mySpacing); + throw std::runtime_error( + "OfdmGenerator::process output size not valid!"); + } + +#ifdef USE_SIMD + for (size_t i = 0, j = 0; i < sizeIn; ) { + // Pack 4 fft operations + typedef struct { + float r[4]; + float i[4]; + } fft_data; + assert(sizeof(FFT_TYPE) == sizeof(fft_data)); + complexf *cplxIn = (complexf*)in; + complexf *cplxOut = (complexf*)out; + fft_data *dataBuffer = (fft_data*)myFftBuffer; + + FFT_REAL(myFftBuffer[0]) = _mm_setzero_ps(); + FFT_IMAG(myFftBuffer[0]) = _mm_setzero_ps(); + for (size_t k = 0; k < myZeroSize; ++k) { + FFT_REAL(myFftBuffer[myZeroDst + k]) = _mm_setzero_ps(); + FFT_IMAG(myFftBuffer[myZeroDst + k]) = _mm_setzero_ps(); + } + for (int k = 0; k < 4; ++k) { + if (i < sizeIn) { + for (size_t l = 0; l < myPosSize; ++l) { + dataBuffer[myPosDst + l].r[k] = cplxIn[i + myPosSrc + l].real(); + dataBuffer[myPosDst + l].i[k] = cplxIn[i + myPosSrc + l].imag(); + } + for (size_t l = 0; l < myNegSize; ++l) { + dataBuffer[myNegDst + l].r[k] = cplxIn[i + myNegSrc + l].real(); + dataBuffer[myNegDst + l].i[k] = cplxIn[i + myNegSrc + l].imag(); + } + i += myNbCarriers; + } else { + for (size_t l = 0; l < myNbCarriers; ++l) { + dataBuffer[l].r[k] = 0.0f; + dataBuffer[l].i[k] = 0.0f; + } + } + } + + kiss_fft(myFftPlan, myFftBuffer, myFftBuffer); + + for (int k = 0; k < 4; ++k) { + if (j < sizeOut) { + for (size_t l = 0; l < mySpacing; ++l) { + cplxOut[j + l].real() = dataBuffer[l].r[k]; + cplxOut[j + l].imag() = dataBuffer[l].i[k]; + } + j += mySpacing; + } + } + } +#else + for (size_t i = 0; i < myNbSymbols; ++i) { + FFT_REAL(myFftBuffer[0]) = 0; + FFT_IMAG(myFftBuffer[0]) = 0; + bzero(&myFftBuffer[myZeroDst], myZeroSize * sizeof(FFT_TYPE)); + memcpy(&myFftBuffer[myPosDst], &in[myPosSrc], + myPosSize * sizeof(FFT_TYPE)); + memcpy(&myFftBuffer[myNegDst], &in[myNegSrc], + myNegSize * sizeof(FFT_TYPE)); + + kiss_fft(myFftPlan, myFftBuffer, out); + + in += myNbCarriers; + out += mySpacing; + } +#endif + + return sizeOut; +} |