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authorTom Rondeau <trondeau@vt.edu>2012-08-09 21:30:50 -0400
committerTom Rondeau <trondeau@vt.edu>2012-08-09 21:30:50 -0400
commit4fcfe4fc01207dfaa941c6b334a7d8e40ccfcb81 (patch)
tree9755e357958abd54fff2cfb0ae0207084d859536 /gr-digital/lib/digital_clock_recovery_mm_cc.cc
parent45502b80d28e2051f5f7780e0c386147f0976798 (diff)
digital: converted clock recovery MM loops (cc and ff).
Diffstat (limited to 'gr-digital/lib/digital_clock_recovery_mm_cc.cc')
-rw-r--r--gr-digital/lib/digital_clock_recovery_mm_cc.cc217
1 files changed, 0 insertions, 217 deletions
diff --git a/gr-digital/lib/digital_clock_recovery_mm_cc.cc b/gr-digital/lib/digital_clock_recovery_mm_cc.cc
deleted file mode 100644
index 198eb4b890..0000000000
--- a/gr-digital/lib/digital_clock_recovery_mm_cc.cc
+++ /dev/null
@@ -1,217 +0,0 @@
-/* -*- c++ -*- */
-/*
- * Copyright 2005,2006,2010,2011 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.
- */
-
-#ifdef HAVE_CONFIG_H
-#include "config.h"
-#endif
-
-#include <gr_io_signature.h>
-#include <gr_prefs.h>
-#include <digital_clock_recovery_mm_cc.h>
-#include <gri_mmse_fir_interpolator_cc.h>
-#include <stdexcept>
-#include <cstdio>
-
-
-// Public constructor
-static const int FUDGE = 16;
-
-digital_clock_recovery_mm_cc_sptr
-digital_make_clock_recovery_mm_cc(float omega, float gain_omega,
- float mu, float gain_mu,
- float omega_relative_limit)
-{
- return gnuradio::get_initial_sptr(new digital_clock_recovery_mm_cc (omega,
- gain_omega,
- mu,
- gain_mu,
- omega_relative_limit));
-}
-
-digital_clock_recovery_mm_cc::digital_clock_recovery_mm_cc (float omega, float gain_omega,
- float mu, float gain_mu,
- float omega_relative_limit)
- : gr_block ("clock_recovery_mm_cc",
- gr_make_io_signature (1, 1, sizeof (gr_complex)),
- gr_make_io_signature2 (1, 2, sizeof (gr_complex), sizeof(float))),
- d_mu (mu), d_omega(omega), d_gain_omega(gain_omega),
- d_omega_relative_limit(omega_relative_limit),
- d_gain_mu(gain_mu), d_last_sample(0), d_interp(new gri_mmse_fir_interpolator_cc()),
- d_verbose(gr_prefs::singleton()->get_bool("clock_recovery_mm_cc", "verbose", false)),
- d_p_2T(0), d_p_1T(0), d_p_0T(0), d_c_2T(0), d_c_1T(0), d_c_0T(0)
-{
- if (omega <= 0.0)
- throw std::out_of_range ("clock rate must be > 0");
- if (gain_mu < 0 || gain_omega < 0)
- throw std::out_of_range ("Gains must be non-negative");
-
- set_omega(omega); // also sets min and max omega
- set_relative_rate (1.0 / omega);
- set_history(3); // ensure 2 extra input sample is available
-}
-
-digital_clock_recovery_mm_cc::~digital_clock_recovery_mm_cc ()
-{
- delete d_interp;
-}
-
-void
-digital_clock_recovery_mm_cc::forecast(int noutput_items, gr_vector_int &ninput_items_required)
-{
- unsigned ninputs = ninput_items_required.size();
- for (unsigned i=0; i < ninputs; i++)
- ninput_items_required[i] =
- (int) ceil((noutput_items * d_omega) + d_interp->ntaps()) + FUDGE;
-}
-
-gr_complex
-digital_clock_recovery_mm_cc::slicer_0deg (gr_complex sample)
-{
- float real=0, imag=0;
-
- if(sample.real() > 0)
- real = 1;
- if(sample.imag() > 0)
- imag = 1;
- return gr_complex(real,imag);
-}
-
-gr_complex
-digital_clock_recovery_mm_cc::slicer_45deg (gr_complex sample)
-{
- float real= -1, imag = -1;
- if(sample.real() > 0)
- real=1;
- if(sample.imag() > 0)
- imag = 1;
- return gr_complex(real,imag);
-}
-
-/*
- Modified Mueller and Muller clock recovery circuit
- Based:
- G. R. Danesfahani, T.G. Jeans, "Optimisation of modified Mueller and Muller
- algorithm," Electronics Letters, Vol. 31, no. 13, 22 June 1995, pp. 1032 - 1033.
-*/
-
-int
-digital_clock_recovery_mm_cc::general_work (int noutput_items,
- gr_vector_int &ninput_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];
- float *foptr = (float *) output_items[1];
-
- bool write_foptr = output_items.size() >= 2;
-
- int ii = 0; // input index
- int oo = 0; // output index
- int ni = ninput_items[0] - d_interp->ntaps() - FUDGE; // don't use more input than this
-
- assert(d_mu >= 0.0);
- assert(d_mu <= 1.0);
-
- float mm_val=0;
- gr_complex u, x, y;
-
- // This loop writes the error to the second output, if it exists
- if (write_foptr) {
- while(oo < noutput_items && ii < ni) {
- d_p_2T = d_p_1T;
- d_p_1T = d_p_0T;
- d_p_0T = d_interp->interpolate (&in[ii], d_mu);
-
- d_c_2T = d_c_1T;
- d_c_1T = d_c_0T;
- d_c_0T = slicer_0deg(d_p_0T);
-
- x = (d_c_0T - d_c_2T) * conj(d_p_1T);
- y = (d_p_0T - d_p_2T) * conj(d_c_1T);
- u = y - x;
- mm_val = u.real();
- out[oo++] = d_p_0T;
-
- // limit mm_val
- mm_val = gr_branchless_clip(mm_val,4.0);
- d_omega = d_omega + d_gain_omega * mm_val;
- d_omega = d_omega_mid + gr_branchless_clip(d_omega-d_omega_mid, d_omega_relative_limit); // make sure we don't walk away
-
- d_mu = d_mu + d_omega + d_gain_mu * mm_val;
- ii += (int)floor(d_mu);
- d_mu -= floor(d_mu);
-
- // write the error signal to the second output
- foptr[oo-1] = mm_val;
-
- if (ii < 0) // clamp it. This should only happen with bogus input
- ii = 0;
- }
- }
- // This loop does not write to the second output (ugly, but faster)
- else {
- while(oo < noutput_items && ii < ni) {
- d_p_2T = d_p_1T;
- d_p_1T = d_p_0T;
- d_p_0T = d_interp->interpolate (&in[ii], d_mu);
-
- d_c_2T = d_c_1T;
- d_c_1T = d_c_0T;
- d_c_0T = slicer_0deg(d_p_0T);
-
- x = (d_c_0T - d_c_2T) * conj(d_p_1T);
- y = (d_p_0T - d_p_2T) * conj(d_c_1T);
- u = y - x;
- mm_val = u.real();
- out[oo++] = d_p_0T;
-
- // limit mm_val
- mm_val = gr_branchless_clip(mm_val,1.0);
-
- d_omega = d_omega + d_gain_omega * mm_val;
- d_omega = d_omega_mid + gr_branchless_clip(d_omega-d_omega_mid, d_omega_relative_limit); // make sure we don't walk away
-
- d_mu = d_mu + d_omega + d_gain_mu * mm_val;
- ii += (int)floor(d_mu);
- d_mu -= floor(d_mu);
-
- if(d_verbose) {
- printf("%f\t%f\n", d_omega, d_mu);
- }
-
- if (ii < 0) // clamp it. This should only happen with bogus input
- ii = 0;
- }
- }
-
- if (ii > 0){
- if (ii > ninput_items[0]){
- fprintf(stderr, "gr_clock_recovery_mm_cc: ii > ninput_items[0] (%d > %d)\n",
- ii, ninput_items[0]);
- assert(0);
- }
- consume_each (ii);
- }
-
- return oo;
-}
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