diff options
Diffstat (limited to 'gr-digital/lib/digital_mpsk_snr_est_cc.cc')
| -rw-r--r-- | gr-digital/lib/digital_mpsk_snr_est_cc.cc | 71 |
1 files changed, 65 insertions, 6 deletions
diff --git a/gr-digital/lib/digital_mpsk_snr_est_cc.cc b/gr-digital/lib/digital_mpsk_snr_est_cc.cc index b71ac0022..b5a60f0d3 100644 --- a/gr-digital/lib/digital_mpsk_snr_est_cc.cc +++ b/gr-digital/lib/digital_mpsk_snr_est_cc.cc @@ -30,12 +30,15 @@ digital_mpsk_snr_est_cc_sptr digital_make_mpsk_snr_est_cc(snr_est_type_t type, + int tag_nsamples, double alpha) { - return gnuradio::get_initial_sptr(new digital_mpsk_snr_est_cc(type, alpha)); + return gnuradio::get_initial_sptr(new digital_mpsk_snr_est_cc( + type, tag_nsamples, alpha)); } digital_mpsk_snr_est_cc::digital_mpsk_snr_est_cc(snr_est_type_t type, + int tag_nsamples, double alpha) : gr_sync_block ("mpsk_snr_est_cc", gr_make_io_signature(1, 1, sizeof(gr_complex)), @@ -44,12 +47,19 @@ digital_mpsk_snr_est_cc::digital_mpsk_snr_est_cc(snr_est_type_t type, d_snr_est = NULL; d_type = type; + d_nsamples = tag_nsamples; + d_count = 0; set_alpha(alpha); set_type(type); // at least 1 estimator has to look back set_history(2); + + std::stringstream str; + str << name() << unique_id(); + d_me = pmt::pmt_string_to_symbol(str.str()); + d_key = pmt::pmt_string_to_symbol("snr"); } digital_mpsk_snr_est_cc::~digital_mpsk_snr_est_cc() @@ -67,8 +77,36 @@ digital_mpsk_snr_est_cc::work(int noutput_items, memcpy(output_items[0], input_items[0], noutput_items * sizeof(gr_complex)); - // Update the SNR estimate registers from the current - return d_snr_est->update(noutput_items, input_items); + const gr_complex *in = (const gr_complex*)input_items[0]; + + // Update, calculate, and issue an SNR tag every d_nsamples + int index = 0, x = 0; + int64_t nwritten = nitems_written(0); + while(index + (d_nsamples-d_count) <= noutput_items) { + x = d_nsamples - d_count; + nwritten += x; + + // Update the SNR estimate registers from the current input + d_snr_est->update(x, &in[index]); + + // Issue a tag with the SNR data + pmt::pmt_t pmt_snr = pmt::pmt_from_double(d_snr_est->snr()); + add_item_tag(0, // stream ID + nwritten, // tag's sample number + d_key, // snr key + pmt_snr, // SNR + d_me); // block src id + + index += x; + d_count = 0; + } + + // Keep track of remaining items and update estimators + x = noutput_items - index; + d_count += x; + d_snr_est->update(x, &in[index]); + + return noutput_items; } double @@ -86,6 +124,12 @@ digital_mpsk_snr_est_cc::type() const return d_type; } +int +digital_mpsk_snr_est_cc::tag_nsample() const +{ + return d_nsamples; +} + double digital_mpsk_snr_est_cc::alpha() const { @@ -119,9 +163,24 @@ digital_mpsk_snr_est_cc::set_type(snr_est_type_t t) } void +digital_mpsk_snr_est_cc::set_tag_nsample(int n) +{ + if(n > 0) { + d_nsamples = n; + d_count = 0; // reset state + } + else + throw std::invalid_argument("digital_mpsk_snr_est_cc: tag_nsamples can't be <= 0\n"); +} + +void digital_mpsk_snr_est_cc::set_alpha(double alpha) { - d_alpha = alpha; - if(d_snr_est) - d_snr_est->set_alpha(d_alpha); + if((alpha >= 0) && (alpha <= 1.0)) { + d_alpha = alpha; + if(d_snr_est) + d_snr_est->set_alpha(d_alpha); + } + else + throw std::invalid_argument("digital_mpsk_snr_est_cc: alpha must be in [0,1]\n"); } |