diff options
Diffstat (limited to 'gr-dtv/lib/atsc/atsc_fpll_impl.cc')
| -rw-r--r-- | gr-dtv/lib/atsc/atsc_fpll_impl.cc | 33 |
1 files changed, 20 insertions, 13 deletions
diff --git a/gr-dtv/lib/atsc/atsc_fpll_impl.cc b/gr-dtv/lib/atsc/atsc_fpll_impl.cc index 71f24713ac..b85a38207d 100644 --- a/gr-dtv/lib/atsc/atsc_fpll_impl.cc +++ b/gr-dtv/lib/atsc/atsc_fpll_impl.cc @@ -41,32 +41,39 @@ int atsc_fpll_impl::work(int noutput_items, gr_vector_const_void_star& input_items, gr_vector_void_star& output_items) { + constexpr float alpha = 0.01; + constexpr float beta = alpha * alpha / 4.0; + const gr_complex* in = (const gr_complex*)input_items[0]; float* out = (float*)output_items[0]; + float a_cos, a_sin; + float x; + gr_complex result, filtered; for (int k = 0; k < noutput_items; k++) { - float a_cos, a_sin; - d_nco.step(); // increment phase d_nco.sincos(&a_sin, &a_cos); // compute cos and sin // Mix out carrier and output I-only signal - gr_complex result = in[k] * gr_complex(a_sin, a_cos); + + // PR Merge Note: Once the Costas Optimization PR #3076 merges, this + // line below helps with performance when cx_limited_range is not available + // such as on Macs and Windows. Once the merge happens I'll push an update. + // gr::fast_cc_multiply(result, in[k], gr_complex(a_sin, a_cos)); + result = in[k] * gr_complex(a_sin, a_cos); + out[k] = result.real(); // Update phase/freq error - gr_complex filtered = d_afc.filter(result); - float x = gr::fast_atan2f(filtered.imag(), filtered.real()); + filtered = d_afc.filter(result); + x = gr::fast_atan2f(filtered.imag(), filtered.real()); // avoid slamming filter with big transitions - static const float limit = GR_M_PI / 2.0; - if (x > limit) - x = limit; - else if (x < -limit) - x = -limit; - - static const float alpha = 0.01; - static const float beta = alpha * alpha / 4.0; + if (x > M_PI_2) + x = M_PI_2; + else if (x < -M_PI_2) + x = -M_PI_2; + d_nco.adjust_phase(alpha * x); d_nco.adjust_freq(beta * x); } |