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Adding an automatic low pass filter for the rational resampler

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This commit is contained in:
Javier Arribas 2018-11-19 17:40:49 +01:00
parent f582a5adba
commit e400319e7e
2 changed files with 24 additions and 4 deletions
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23
src/algorithms/resampler/adapters/mmse_resampler_conditioner.cc
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@ -63,6 +63,17 @@ MmseResamplerConditioner::MmseResamplerConditioner(
if (item_type_.compare("gr_complex") == 0)
{
item_size_ = sizeof(gr_complex);
//create a FIR low pass filter
std::vector<float> taps = gr::filter::firdes::low_pass(1.0,
sample_freq_in_,
sample_freq_out_ / 2.1,
sample_freq_out_ / 10,
gr::filter::firdes::win_type::WIN_HAMMING);
std::cout << "Enabled fractional resampler low pass filter with " << taps.size() << " taps" << std::endl;
fir_filter_ccf_ = gr::filter::fir_filter_ccf::make(1, taps);
#ifdef GR_GREATER_38
resampler_ = gr::filter::mmse_resampler_cc::make(0.0, sample_freq_in_ / sample_freq_out_);
#else
@ -96,18 +107,17 @@ MmseResamplerConditioner::MmseResamplerConditioner(
MmseResamplerConditioner::~MmseResamplerConditioner() {}
void MmseResamplerConditioner::connect(gr::top_block_sptr top_block)
{
if (dump_)
{
top_block->connect(fir_filter_ccf_, 0, resampler_, 0);
top_block->connect(resampler_, 0, file_sink_, 0);
DLOG(INFO) << "connected resampler to file sink";
}
else
{
DLOG(INFO) << "nothing to connect internally";
top_block->connect(fir_filter_ccf_, 0, resampler_, 0);
}
}
@ -116,14 +126,19 @@ void MmseResamplerConditioner::disconnect(gr::top_block_sptr top_block)
{
if (dump_)
{
top_block->disconnect(fir_filter_ccf_, 0, resampler_, 0);
top_block->disconnect(resampler_, 0, file_sink_, 0);
}
else
{
top_block->disconnect(fir_filter_ccf_, 0, resampler_, 0);
}
}
gr::basic_block_sptr MmseResamplerConditioner::get_left_block()
{
return resampler_;
return fir_filter_ccf_;
}

5
src/algorithms/resampler/adapters/mmse_resampler_conditioner.h
View File

@ -36,9 +36,13 @@
#include "gnss_block_interface.h"
#ifdef GR_GREATER_38
#include <gnuradio/filter/mmse_resampler_cc.h>
#include <gnuradio/filter/fir_filter_blk.h>
#else
#include <gnuradio/filter/fractional_resampler_cc.h>
#include <gnuradio/filter/fir_filter_ccf.h>
#endif
#include <gnuradio/filter/firdes.h>
#include <string>
class ConfigurationInterface;
@ -91,6 +95,7 @@ private:
#else
gr::filter::fractional_resampler_cc::sptr resampler_;
#endif
gr::filter::fir_filter_ccf::sptr fir_filter_ccf_;
gr::block_sptr file_sink_;
};