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Diffstat (limited to 'gr-channels/lib/selective_fading_model_impl.cc')
| -rw-r--r-- | gr-channels/lib/selective_fading_model_impl.cc | 169 |
1 files changed, 169 insertions, 0 deletions
diff --git a/gr-channels/lib/selective_fading_model_impl.cc b/gr-channels/lib/selective_fading_model_impl.cc new file mode 100644 index 0000000000..7beebf2e65 --- /dev/null +++ b/gr-channels/lib/selective_fading_model_impl.cc @@ -0,0 +1,169 @@ +/* -*- c++ -*- */ +/* + * Copyright 2013 Free Software Foundation, Inc. + * + * This file is part of GNU Radio + * + * GNU Radio 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, or (at your option) + * any later version. + * + * GNU Radio 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 GNU Radio; see the file COPYING. If not, write to + * the Free Software Foundation, Inc., 51 Franklin Street, + * Boston, MA 02110-1301, USA. + */ + +#include "selective_fading_model_impl.h" +#include <gnuradio/io_signature.h> +#include <iostream> + +#include <boost/format.hpp> +#include <boost/random.hpp> + +#include <gnuradio/fxpt.h> +#include <sincostable.h> + + +// FASTSINCOS: 0 = slow native, 1 = gr::fxpt impl, 2 = sincostable.h +#define FASTSINCOS 2 + + +namespace gr { + namespace channels { + + selective_fading_model::sptr + selective_fading_model::make( unsigned int N, float fDTs, bool LOS, float K, int seed, std::vector<float> delays, std::vector<float> mags, int ntaps) + { + return gnuradio::get_initial_sptr + (new selective_fading_model_impl( N, fDTs, LOS, K, seed, delays, mags, ntaps)); + } + + // Block constructor + selective_fading_model_impl::selective_fading_model_impl( unsigned int N, float fDTs, bool LOS, float K, int seed, std::vector<float> delays, std::vector<float> mags, int ntaps ) + : sync_block("selective_fading_model", + io_signature::make(1, 1, sizeof(gr_complex)), + io_signature::make(1, 1, sizeof(gr_complex))), + d_delays(delays), + d_mags(mags), + d_sintable(1024) + { + if(mags.size() != delays.size()) + throw std::runtime_error("magnitude and delay vectors must be the same length!"); + + for(size_t i=0; i<mags.size(); i++){ + d_faders.push_back(new gr::channels::flat_fader_impl(N,fDTs, LOS, K, seed+i)); + } + + // set up tap history +// int ntaps = 10; + set_history(1+ntaps); + d_taps.resize(ntaps, gr_complex(0,0)); + } + + selective_fading_model_impl::~selective_fading_model_impl() + { + for(size_t i=0; i<d_faders.size(); i++){ + delete d_faders[i]; + } + } + + int + selective_fading_model_impl::work (int noutput_items, + gr_vector_const_void_star &input_items, + gr_vector_void_star &output_items) + { + const gr_complex* in = (const gr_complex*) input_items[0]; + gr_complex* out = (gr_complex*) output_items[0]; + + // loop over each output sample + for(int i=0; i<noutput_items; i++){ + + // clear the current values in each tap + for(size_t j=0; j<d_taps.size(); j++){ + d_taps[j] = gr_complex(0,0); + } + + // add each flat fading component to the taps + for(size_t j=0; j<d_faders.size(); j++){ + gr_complex ff_H(d_faders[j]->next_sample()); + for(size_t k=0; k<d_taps.size(); k++){ + float dist = k-d_delays[j]; + float interpmag = d_sintable.sinc(2*M_PI*dist); + d_taps[k] += ff_H * interpmag * d_mags[j]; + } + } + + // apply the taps and generate output + gr_complex sum(0,0); + for(size_t j=0; j<d_taps.size(); j++){ + sum += in[i+j] * d_taps[d_taps.size()-j-1]; + } + + // assign output + out[i] = sum; + } + + // return all outputs + return noutput_items; + } + + void + selective_fading_model_impl::setup_rpc() + { +#ifdef GR_CTRLPORT + add_rpc_variable( + rpcbasic_sptr(new rpcbasic_register_get<selective_fading_model, float >( + alias(), "fDTs", + &selective_fading_model::fDTs, + pmt::mp(0), pmt::mp(1), pmt::mp(0.01), + "Hz*Sec", "normalized maximum doppler frequency (fD*Ts)", + RPC_PRIVLVL_MIN, DISPTIME | DISPOPTSTRIP))); + add_rpc_variable( + rpcbasic_sptr(new rpcbasic_register_set<selective_fading_model, float >( + alias(), "fDTs", + &selective_fading_model::set_fDTs, + pmt::mp(0), pmt::mp(1), pmt::mp(0.01), + "Hz*Sec", "normalized maximum doppler frequency (fD*Ts)", + RPC_PRIVLVL_MIN, DISPTIME | DISPOPTSTRIP))); + + add_rpc_variable( + rpcbasic_sptr(new rpcbasic_register_get<selective_fading_model, float >( + alias(), "K", + &selective_fading_model::K, + pmt::mp(0), pmt::mp(8), pmt::mp(4), + "Ratio", "Rician factor (ratio of the specular power to the scattered power)", + RPC_PRIVLVL_MIN, DISPTIME | DISPOPTSTRIP))); + add_rpc_variable( + rpcbasic_sptr(new rpcbasic_register_set<selective_fading_model, float >( + alias(), "K", + &selective_fading_model::set_K, + pmt::mp(0), pmt::mp(8), pmt::mp(4), + "Ratio", "Rician factor (ratio of the specular power to the scattered power)", + RPC_PRIVLVL_MIN, DISPTIME | DISPOPTSTRIP))); + + add_rpc_variable( + rpcbasic_sptr(new rpcbasic_register_get<selective_fading_model, float >( + alias(), "step", + &selective_fading_model::step, + pmt::mp(0), pmt::mp(8), pmt::mp(4), + "radians", "Maximum step size for random walk angle per sample", + RPC_PRIVLVL_MIN, DISPTIME | DISPOPTSTRIP))); + add_rpc_variable( + rpcbasic_sptr(new rpcbasic_register_set<selective_fading_model, float >( + alias(), "step", + &selective_fading_model::set_step, + pmt::mp(0), pmt::mp(1), pmt::mp(0.00001), + "radians", "Maximum step size for random walk angle per sample", + RPC_PRIVLVL_MIN, DISPTIME | DISPOPTSTRIP))); +#endif /* GR_CTRLPORT */ + } + + } /* namespace channels */ +} /* namespace gr */ |