Add ChannelDecimator decimate by 2 and no-shift options.

This commit is contained in:
Jared Boone 2015-11-19 12:24:20 -08:00
parent ccd64f3cd9
commit 060da5d227
2 changed files with 29 additions and 14 deletions

View File

@ -39,14 +39,10 @@ buffer_c16_t ChannelDecimator::execute_decimation(buffer_c8_t buffer) {
* -> gain of 256 * -> gain of 256
* -> decimation by 2 * -> decimation by 2
* -> 1.544MHz complex<int16_t>[1024], [-32768, 32512] */ * -> 1.544MHz complex<int16_t>[1024], [-32768, 32512] */
const auto stage_0_out = translate.execute(buffer, work_baseband_buffer); auto stage_0_out = execute_stage_0(buffer, work_baseband_buffer);
if( decimation_factor == DecimationFactor::By2 ) {
//if( fs_over_4_downconvert ) { return stage_0_out;
// // TODO: }
//} else {
// Won't work until cic_0 will accept input type of buffer_c8_t.
// stage_0_out = cic_0.execute(buffer, work_baseband_buffer);
//}
/* 1.536MHz complex<int16_t>[1024], [-32768, 32512] /* 1.536MHz complex<int16_t>[1024], [-32768, 32512]
* -> 3rd order CIC: -0.1dB @ 0.028fs, -1dB @ 0.088fs, -60dB @ 0.468fs * -> 3rd order CIC: -0.1dB @ 0.028fs, -1dB @ 0.088fs, -60dB @ 0.468fs
@ -82,3 +78,14 @@ buffer_c16_t ChannelDecimator::execute_decimation(buffer_c8_t buffer) {
return cic_4_out; return cic_4_out;
} }
buffer_c16_t ChannelDecimator::execute_stage_0(
buffer_c8_t buffer,
buffer_c16_t work_baseband_buffer
) {
if( fs_over_4_downconvert ) {
return translate.execute(buffer, work_baseband_buffer);
} else {
return cic_0.execute(buffer, work_baseband_buffer);
}
}

View File

@ -32,6 +32,7 @@
class ChannelDecimator { class ChannelDecimator {
public: public:
enum class DecimationFactor { enum class DecimationFactor {
By2,
By4, By4,
By8, By8,
By16, By16,
@ -39,13 +40,16 @@ public:
}; };
constexpr ChannelDecimator( constexpr ChannelDecimator(
) : decimation_factor { DecimationFactor::By32 } ) : decimation_factor { DecimationFactor::By32 },
fs_over_4_downconvert { true }
{ {
} }
constexpr ChannelDecimator( constexpr ChannelDecimator(
const DecimationFactor decimation_factor const DecimationFactor decimation_factor,
) : decimation_factor { decimation_factor } const bool fs_over_4_downconvert = true
) : decimation_factor { decimation_factor },
fs_over_4_downconvert { fs_over_4_downconvert }
{ {
} }
@ -62,18 +66,22 @@ public:
private: private:
std::array<complex16_t, 1024> work_baseband; std::array<complex16_t, 1024> work_baseband;
//const bool fs_over_4_downconvert = true;
dsp::decimate::TranslateByFSOver4AndDecimateBy2CIC3 translate; dsp::decimate::TranslateByFSOver4AndDecimateBy2CIC3 translate;
//dsp::decimate::DecimateBy2CIC3 cic_0; dsp::decimate::Complex8DecimateBy2CIC3 cic_0;
dsp::decimate::DecimateBy2CIC3 cic_1; dsp::decimate::DecimateBy2CIC3 cic_1;
dsp::decimate::DecimateBy2CIC3 cic_2; dsp::decimate::DecimateBy2CIC3 cic_2;
dsp::decimate::DecimateBy2CIC3 cic_3; dsp::decimate::DecimateBy2CIC3 cic_3;
dsp::decimate::DecimateBy2CIC3 cic_4; dsp::decimate::DecimateBy2CIC3 cic_4;
DecimationFactor decimation_factor; DecimationFactor decimation_factor;
const bool fs_over_4_downconvert;
buffer_c16_t execute_decimation(buffer_c8_t buffer); buffer_c16_t execute_decimation(buffer_c8_t buffer);
buffer_c16_t execute_stage_0(
buffer_c8_t buffer,
buffer_c16_t work_baseband_buffer
);
}; };
#endif/*__CHANNEL_DECIMATOR_H__*/ #endif/*__CHANNEL_DECIMATOR_H__*/