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[Commit-gnuradio] r4207 - gnuradio/branches/developers/trondeau/digital-
|
From: |
trondeau |
|
Subject: |
[Commit-gnuradio] r4207 - gnuradio/branches/developers/trondeau/digital-wip2/gnuradio-core/src/lib/general |
|
Date: |
Mon, 1 Jan 2007 12:41:54 -0700 (MST) |
Author: trondeau
Date: 2007-01-01 12:41:54 -0700 (Mon, 01 Jan 2007)
New Revision: 4207
Added:
gnuradio/branches/developers/trondeau/digital-wip2/gnuradio-core/src/lib/general/gr_mpsk_receiver_cc.cc
gnuradio/branches/developers/trondeau/digital-wip2/gnuradio-core/src/lib/general/gr_mpsk_receiver_cc.h
gnuradio/branches/developers/trondeau/digital-wip2/gnuradio-core/src/lib/general/gr_mpsk_receiver_cc.i
Modified:
gnuradio/branches/developers/trondeau/digital-wip2/gnuradio-core/src/lib/general/Makefile.am
gnuradio/branches/developers/trondeau/digital-wip2/gnuradio-core/src/lib/general/general.i
Log:
adding new M-PSK receiver that does symbol, phase, and frequency
synchronization together. This has been tested in a loopback setting
(non-over-the-air) for BPSK, QPSK, and 8PSK.
Modified:
gnuradio/branches/developers/trondeau/digital-wip2/gnuradio-core/src/lib/general/Makefile.am
===================================================================
---
gnuradio/branches/developers/trondeau/digital-wip2/gnuradio-core/src/lib/general/Makefile.am
2006-12-30 15:45:46 UTC (rev 4206)
+++
gnuradio/branches/developers/trondeau/digital-wip2/gnuradio-core/src/lib/general/Makefile.am
2007-01-01 19:41:54 UTC (rev 4207)
@@ -158,6 +158,7 @@
gr_map_bb.cc \
gr_math.cc \
gr_misc.cc \
+ gr_mpsk_receiver_cc.cc \
gr_nlog10_ff.cc \
gr_nop.cc \
gr_null_sink.cc \
@@ -284,6 +285,7 @@
gr_map_bb.h \
gr_math.h \
gr_misc.h \
+ gr_mpsk_receiver_cc.h \
gr_nco.h \
gr_nlog10_ff.h \
gr_noise_type.h \
@@ -416,6 +418,7 @@
gr_lms_dfe_cc.i \
gr_lms_dfe_ff.i \
gr_map_bb.i \
+ gr_mpsk_receiver_cc.i \
gr_nlog10_ff.i \
gr_nop.i \
gr_null_sink.i \
Modified:
gnuradio/branches/developers/trondeau/digital-wip2/gnuradio-core/src/lib/general/general.i
===================================================================
---
gnuradio/branches/developers/trondeau/digital-wip2/gnuradio-core/src/lib/general/general.i
2006-12-30 15:45:46 UTC (rev 4206)
+++
gnuradio/branches/developers/trondeau/digital-wip2/gnuradio-core/src/lib/general/general.i
2007-01-01 19:41:54 UTC (rev 4207)
@@ -71,6 +71,7 @@
#include <gr_nlog10_ff.h>
#include <gr_fake_channel_coder_pp.h>
#include <gr_throttle.h>
+#include <gr_mpsk_receiver_cc.h>
#include <gr_stream_to_streams.h>
#include <gr_streams_to_stream.h>
#include <gr_streams_to_vector.h>
@@ -165,6 +166,7 @@
%include "gr_nlog10_ff.i"
%include "gr_fake_channel_coder_pp.i"
%include "gr_throttle.i"
+%include "gr_mpsk_receiver_cc.i"
%include "gr_stream_to_streams.i"
%include "gr_streams_to_stream.i"
%include "gr_streams_to_vector.i"
Added:
gnuradio/branches/developers/trondeau/digital-wip2/gnuradio-core/src/lib/general/gr_mpsk_receiver_cc.cc
===================================================================
---
gnuradio/branches/developers/trondeau/digital-wip2/gnuradio-core/src/lib/general/gr_mpsk_receiver_cc.cc
(rev 0)
+++
gnuradio/branches/developers/trondeau/digital-wip2/gnuradio-core/src/lib/general/gr_mpsk_receiver_cc.cc
2007-01-01 19:41:54 UTC (rev 4207)
@@ -0,0 +1,295 @@
+/* -*- c++ -*- */
+/*
+ * Copyright 2005,2006 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 2, 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 <gr_timing_recovery_simple_cc.h>
+#include <stdexcept>
+#include <gr_math.h>
+#include <gr_expj.h>
+#include <gri_mmse_fir_interpolator_cc.h>
+
+
+#define M_TWOPI (2*M_PI)
+
+
+// Public constructor
+
+gr_timing_recovery_simple_cc_sptr
+gr_make_timing_recovery_simple_cc(unsigned int M, float theta,
+ float alpha, float beta,
+ float fmin, float fmax,
+ float mu, float gain_mu,
+ float omega, float gain_omega, float
omega_rel)
+{
+ return gr_timing_recovery_simple_cc_sptr (new gr_timing_recovery_simple_cc
(M, theta,
+
alpha, beta,
+
fmin, fmax,
+
mu, gain_mu,
+
omega, gain_omega, omega_rel));
+}
+
+gr_timing_recovery_simple_cc::gr_timing_recovery_simple_cc (unsigned int M,
float theta,
+ float alpha, float
beta,
+ float fmin, float
fmax,
+ float mu, float
gain_mu,
+ float omega, float
gain_omega, float omega_rel)
+ : gr_block ("timing_recovery_simple_cc",
+ gr_make_io_signature (1, 1, sizeof (gr_complex)),
+ gr_make_io_signature (1, 1, sizeof (gr_complex))),
+ d_M(M), d_theta(theta),
+ d_alpha(alpha), d_beta(beta), d_freq(0), d_phase(0),
+ d_mu(mu), d_gain_mu(gain_mu), d_gain_omega(gain_omega),
+ d_max_omega(omega+omega_rel), d_min_omega(omega-omega_rel),
+ d_p_2T(0), d_p_1T(0), d_p_0T(0), d_c_2T(0), d_c_1T(0), d_c_0T(0)
+{
+ d_interp = new gri_mmse_fir_interpolator_cc();
+ d_dl_idx = 0;
+
+ set_omega(omega);
+
+ // Select a phase detector and a decision maker for the modulation order
+ switch(d_M) {
+ case 2: // optimized algorithms for BPSK
+ d_phase_error_detector =
&gr_timing_recovery_simple_cc::phase_error_detector_bpsk;
+ d_decision = &gr_timing_recovery_simple_cc::decision_bpsk;
+ break;
+
+ case 4: // optimized algorithms for QPSK
+ d_phase_error_detector =
&gr_timing_recovery_simple_cc::phase_error_detector_qpsk;
+ d_decision = &gr_timing_recovery_simple_cc::decision_qpsk;
+ break;
+
+ default: // generic algorithms for any M (power of 2?) but not pretty
+ d_phase_error_detector =
&gr_timing_recovery_simple_cc::phase_error_detector_generic;
+ d_decision = &gr_timing_recovery_simple_cc::decision_generic;
+ break;
+ }
+
+ // FIXME: remove when we've got everything working
+ fout.open("timing_recovery.txt");
+}
+
+gr_timing_recovery_simple_cc::~gr_timing_recovery_simple_cc ()
+{
+ // FIXME: remove when we've got everything working
+ fout.close();
+ delete d_interp;
+}
+
+void
+gr_timing_recovery_simple_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] = d_samples_per_symbol+d_offset;
+}
+
+float
+gr_timing_recovery_simple_cc::phase_error_detector_qpsk(gr_complex sample)
const
+{
+ return ((sample.real()>0 ? 1.0 : -1.0) * sample.imag() -
+ (sample.imag()>0 ? 1.0 : -1.0) * sample.real());
+}
+
+float
+gr_timing_recovery_simple_cc::phase_error_detector_bpsk(gr_complex sample)
const
+{
+ return (sample.real()*sample.imag());
+}
+
+float gr_timing_recovery_simple_cc::phase_error_detector_generic(gr_complex
sample) const
+{
+ unsigned int min_m = 0;
+ gr_complex constpoint;
+ float min_s = 65535;
+ float error = 0;
+
+ // Develop all possible constellation points and find the one that minimizes
+ // the Euclidean distance (error) with the sample
+ for(unsigned int m=0; m < d_M; m++) {
+ constpoint = gr_expj((M_TWOPI/d_M)*m + d_theta);
+ gr_complex diff = (constpoint - sample)*(constpoint - sample);
+
+ if(fabs(diff.real()) < min_s) {
+ min_s = fabs(diff.real());
+ min_m = m;
+ }
+ }
+ // Use this constellation point to derotate the sample
+ constpoint = gr_expj(-((M_TWOPI/d_M)*min_m + d_theta));
+ // get the error in the sample as the phase difference from the real axis
+ error = gr_fast_atan2f(sample*constpoint);
+
+ return error;
+}
+
+gr_complex
+gr_timing_recovery_simple_cc::decision_bpsk(gr_complex sample) const
+{
+ float real=-0.5, imag=0.0;
+
+ // Implements a 1-demensional slicer
+ if(sample.real() > 0)
+ real = 0.5;
+ return gr_complex(real,imag);
+}
+
+gr_complex
+gr_timing_recovery_simple_cc::decision_qpsk(gr_complex sample) const
+{
+ float real=-0.5, imag=-0.5;
+
+ // Implements a simple slicer function
+ if(sample.real() > 0)
+ real = 0.5;
+ if(sample.imag() > 0)
+ imag = 0.5;
+ return gr_complex(real,imag);
+}
+
+gr_complex
+gr_timing_recovery_simple_cc::decision_generic(gr_complex sample) const
+{
+ unsigned int min_m = 0;
+ gr_complex constpoint;
+ float min_s = 65535;
+
+ // Develop all possible constellation points and find the one that minimizes
+ // the Euclidean distance (error) with the sample
+ for(unsigned int m=0; m < d_M; m++) {
+ constpoint = gr_expj((M_TWOPI/d_M)*m + d_theta);
+ gr_complex diff = (constpoint - sample)*(constpoint - sample);
+
+ if(fabs(diff.real()) < min_s) {
+ min_s = fabs(diff.real());
+ min_m = m;
+ }
+ }
+ // Return the constellation point that minimizes the error
+ constpoint = gr_expj(((M_TWOPI/d_M)*min_m + d_theta));
+ return constpoint;
+}
+
+int
+gr_timing_recovery_simple_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 phase_error = 0, mm_error = 0;
+ gr_complex sample, nco, u, x, y;
+
+ int i=0, o=0;
+
+ while(i < ninput_items[0]) {
+
+ while((d_mu > 1) && (i < ninput_items[0])) {
+ d_mu--; // skip a number of symbols between sampling
+ d_phase += d_freq; // increment the phase based on the frequency of the
rotation
+
+ // Keep phase clamped and not walk to infinity
+ while(d_phase>M_TWOPI)
+ d_phase -= M_TWOPI;
+ while(d_phase<-M_TWOPI)
+ d_phase += M_TWOPI;
+
+ nco = gr_expj(-d_phase); // get the NCO value for derotating the current
sample
+ sample = nco*in[i]; // get the downconverted symbol
+
+ // Fill up the delay line for the interpolator
+ d_dl[d_dl_idx] = sample;
+ d_dl[(d_dl_idx + DLLEN)] = sample; // put this in the second half of
the buffer for overflows
+ d_dl_idx = (d_dl_idx+1) % DLLEN; // Keep the delay line index in
bounds
+
+ #if 0
+ // FIXME: remove when we've got everything working
+ fout << d_mu << "\t" << sample.real() << " " << sample.imag();
+ if(d_mu < 1)
+ fout << "\t" << sample.real() << " " << sample.imag() << std::endl;
+ else
+ fout << "0 0" << std::endl;
+ #endif
+
+ i++;
+ }
+
+ if(i < ninput_items[0]) {
+ d_offset = d_samples_per_symbol;
+ gr_complex interp_sample = d_interp->interpolate(&d_dl[d_dl_idx], d_mu);
+
+ // Make sample timing corrections
+ d_p_2T = d_p_1T;
+ d_p_1T = d_p_0T;
+ d_p_0T = interp_sample;
+
+ d_c_2T = d_c_1T;
+ d_c_1T = d_c_0T;
+ d_c_0T = (*this.*d_decision)(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_error = u.real();
+
+ // limit mm_val
+ if (mm_error > 1.0)
+ mm_error = 1.0;
+ else if (mm_error < -1.0)
+ mm_error = -1.0;
+
+ d_omega = d_omega + d_gain_omega * mm_error;
+ if (d_omega > d_max_omega)
+ d_omega = d_max_omega;
+ else if (d_omega < d_min_omega)
+ d_omega = d_min_omega;
+
+ d_mu += d_omega + d_gain_mu * mm_error;
+
+ #if 0
+ printf("samples: %f+j%f mu: %f omega: %f mm_error: %f\n",
+ interp_sample.real(), interp_sample.imag(), d_mu, d_omega,
mm_error);
+ #endif
+
+ // Make phase and frequency corrections based on sampled value
+ phase_error = (*this.*d_phase_error_detector)(interp_sample);
+ d_freq += d_beta*phase_error;
+ d_phase += d_alpha*phase_error;
+
+ // FIXME: Add frequency clamping
+
+ out[o++] = d_p_0T; //interp_sample;
+ }
+
+ //printf("\t interpolated sample: %f+j*%f\n\n", interp_sample.real(),
interp_sample.imag());
+ }
+
+ consume_each(i);
+ return o;
+}
Added:
gnuradio/branches/developers/trondeau/digital-wip2/gnuradio-core/src/lib/general/gr_mpsk_receiver_cc.h
===================================================================
---
gnuradio/branches/developers/trondeau/digital-wip2/gnuradio-core/src/lib/general/gr_mpsk_receiver_cc.h
(rev 0)
+++
gnuradio/branches/developers/trondeau/digital-wip2/gnuradio-core/src/lib/general/gr_mpsk_receiver_cc.h
2007-01-01 19:41:54 UTC (rev 4207)
@@ -0,0 +1,307 @@
+/* -*- c++ -*- */
+/*
+ * Copyright 2004 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 2, 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.
+ */
+
+#ifndef INCLUDED_GR_TIMING_RECOVERY_SIMPLE_CC_H
+#define INCLUDED_GR_TIMING_RECOVERY_SIMPLE_CC_H
+
+#include <gr_block.h>
+#include <gr_complex.h>
+#include <fstream>
+
+class gri_mmse_fir_interpolator_cc;
+
+class gr_timing_recovery_simple_cc;
+typedef boost::shared_ptr<gr_timing_recovery_simple_cc>
gr_timing_recovery_simple_cc_sptr;
+
+// public constructor
+gr_timing_recovery_simple_cc_sptr
+gr_make_timing_recovery_simple_cc (unsigned int M, float theta,
+ float alpha, float beta,
+ float fmin, float fmax,
+ float mu, float gain_mu,
+ float omega, float gain_omega, float
omega_rel);
+
+/*!
+ * \brief This block takes care of receiving M-PSK modulated signals through
phase, frequency, and symbol
+ * synchronization.
+ * \ingroup block
+ *
+ * This block takes care of receiving M-PSK modulated signals through phase,
frequency, and symbol
+ * synchronization. It performs carrier frequency and phase locking as well as
symbol timing recovery.
+ * It works with (D)BPSK, (D)QPSK, and (D)8PSK as tested currently. It should
also work for OQPSK and
+ * PI/4 DQPSK.
+ *
+ * The phase and frequency synchronization are based on a Costas loop that
finds the error of the incoming
+ * signal point compared to its nearest constellation point. The frequency and
phase of the NCO are
+ * updated according to this error. There are optimized phase error detectors
for BPSK and QPSK, but 8PSK
+ * is done using a brute-force computation of the constellation points to find
the minimum.
+ *
+ * The symbol synchronization is done using a modified Mueller and Muller
circuit from the paper:
+ *
+ * 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.
+ *
+ * This circuit interpolates the downconverted sample (using the NCO developed
by the Costas loop)
+ * every mu samples, then it finds the sampling error based on this and the
past symbols and the decision
+ * made on the samples. Like the phase error detector, there are optimized
decision algorithms for BPSK
+ * and QPKS, but 8PSK uses another brute force computation against all
possible symbols. The modifications
+ * to the M&M used here reduce self-noise.
+ *
+ */
+
+class gr_timing_recovery_simple_cc : public gr_block
+{
+ public:
+ ~gr_timing_recovery_simple_cc ();
+ void forecast(int noutput_items, gr_vector_int &ninput_items_required);
+ int general_work (int noutput_items,
+ gr_vector_int &ninput_items,
+ gr_vector_const_void_star &input_items,
+ gr_vector_void_star &output_items);
+
+
+ // Member functions related to the symbol tracking portion of the receiver
+ //! (M&M) Returns current value of mu
+ float mu() const { return d_mu;}
+
+ //! (M&M) Returns current value of omega
+ float omega() const { return d_omega;}
+
+ //! (M&M) Returns mu gain factor
+ float gain_mu() const { return d_gain_mu;}
+
+ //! (M&M) Returns omega gain factor
+ float gain_omega() const { return d_gain_omega;}
+
+ //! (M&M) Sets value of mu
+ void set_mu (float mu) { d_mu = mu; }
+
+ //! (M&M) Sets value of omega and its min and max values
+ void set_omega (float omega) {
+ d_omega = omega;
+ d_min_omega = omega*(1.0 - d_omega_rel);
+ d_max_omega = omega*(1.0 + d_omega_rel);
+ }
+
+ //! (M&M) Sets value for mu gain factor
+ void set_gain_mu (float gain_mu) { d_gain_mu = gain_mu; }
+
+ //! (M&M) Sets value for omega gain factor
+ void set_gain_omega (float gain_omega) { d_gain_omega = gain_omega; }
+
+
+
+ // Member function related to the phase/frequency tracking portion of the
receiver
+ //! (CL) Returns the value for alpha (the phase gain term)
+ float alpha() const { return d_alpha; }
+
+ //! (CL) Returns the value of beta (the frequency gain term)
+ float beta() const { return d_beta; }
+
+ //! (CL) Returns the current value of the frequency of the NCO in the Costas
loop
+ float freq() const { return d_freq; }
+
+ //! (CL) Returns the current value of the phase of the NCO in the Costal loop
+ float phase() const { return d_phaes; }
+
+ //! (CL) Sets the value for alpha (the phase gain term)
+ void set_alpha(float alpha) { d_alpha = alpha; }
+
+ //! (CL) Setss the value of beta (the frequency gain term)
+ float set_beta(float beta) { d_beta = beta; }
+
+ //! (CL) Sets the current value of the frequency of the NCO in the Costas
loop
+ float set_freq(float freq) { d_freq = freq; }
+
+ //! (CL) Setss the current value of the phase of the NCO in the Costal loop
+ float set_phase(float phase) { d_phaes = phase; }
+
+
+protected:
+
+ /*!
+ * \brief Constructor to synchronize incoming M-PSK symbols
+ *
+ * \param M modulation order of the M-PSK modulation
+ * \param theta any constant phase rotation from the real axis of the
constellation
+ * \param alpha gain parameter to adjust the phase in the Costas loop
(~0.01)
+ * \param beta gain parameter to adjust the frequency in the Costas
loop (~alpha^2/4)
+ * \param fmin minimum normalized frequency value the loop can achieve
+ * \param fmax maximum normalized frequency value the loop can achieve
+ * \param mu initial parameter for the interpolator [0,1]
+ * \param gain_mu gain parameter of the M&M error signal to adjust mu
(~0.05)
+ * \param omega initial value for the number of symbols between
samples (~number of samples/symbol)
+ * \param gain_omega gain parameter to adjust omega based on the error
(~omega^2/4)
+ * \param omega_rel sets the maximum (omega*(1+omega_rel)) and minimum
(omega*(1+omega_rel)) omega (~0.005)
+ *
+ * The constructor also chooses which phase detector and decision maker to
use in the work loop based on the
+ * value of M.
+ */
+ gr_timing_recovery_simple_cc (unsigned int M, float theta,
+ float alpha, float beta,
+ float fmin, float fmax,
+ float mu, float gain_mu,
+ float omega, float gain_omega, float omega_rel);
+
+/*!
+ * \brief Phase error detector for MPSK modulations.
+ *
+ * \param sample the I&Q sample from which to determine the phase error
+ *
+ * This function determines the phase error for any MPSK signal by creating
a set of PSK constellation points
+ * and doing a brute-force search to see which point minimizes the Euclidean
distance. This point is then used
+ * to derotate the sample to the real-axis and a atan (using the fast
approximation function) to determine the
+ * phase difference between the incoming sample and the real constellation
point
+ *
+ * This should be cleaned up and made more efficient.
+ *
+ * \returns the approximated phase error.
+ */
+ float phase_error_detector_generic(gr_complex sample) const; // generic for
M but more costly
+
+ /*!
+ * \brief Phase error detector for BPSK modulation.
+ *
+ * \param sample the I&Q sample from which to determine the phase error
+ *
+ * This function determines the phase error using a simple BPSK phase error
detector by multiplying the real
+ * and imaginary (the error signal) components together. As the imaginary
part goes to 0, so does this error.
+ *
+ * \returns the approximated phase error.
+ */
+ float phase_error_detector_bpsk(gr_complex sample) const; // optimized
for BPSK
+
+ /*!
+ * \brief Phase error detector for QPSK modulation.
+ *
+ * \param sample the I&Q sample from which to determine the phase error
+ *
+ * This function determines the phase error using the limiter approach in a
standard 4th order Costas loop
+ *
+ * \returns the approximated phase error.
+ */
+ float phase_error_detector_qpsk(gr_complex sample) const;
+
+
+
+ /*!
+ * \brief Decision maker for a generic MPSK constellation.
+ *
+ * \param sample the baseband I&Q sample from which to make the decision
+ *
+ * This decision maker is a generic implementation the creates a set of
constellation point for MPSK
+ * and does a brute-force search for the constellation point that minimizes
the error from the incoming
+ * signal.
+ *
+ * \returns the constellation point that minimizes error.
+ */
+ gr_complex decision_generic(gr_complex sample) const;
+
+
+ /*!
+ * \brief Decision maker for BPSK constellation.
+ *
+ * \param sample the baseband I&Q sample from which to make the decision
+ *
+ * This decision maker is a simple slicer function that makes a decision on
the symbol based on its
+ * placement on the real axis of greater than 0 or less than 0; the
quadrature component is always 0.
+ *
+ * \returns the constellation point that minimizes error.
+ */
+ gr_complex decision_bpsk(gr_complex sample) const;
+
+
+ /*!
+ * \brief Decision maker for QPSK constellation.
+ *
+ * \param sample the baseband I&Q sample from which to make the decision
+ *
+ * This decision maker is a simple slicer function that makes a decision on
the symbol based on its
+ * placement versus both axes and returns which quadrant the symbol is in.
+ *
+ * \returns the constellation point that minimizes error.
+ */
+ gr_complex decision_qpsk(gr_complex sample) const;
+
+ private:
+ unsigned int d_M;
+ float d_theta;
+
+ // Members related to carrier and phase tracking
+ float d_alpha;
+ float d_beta;
+ float d_freq;
+ float d_phase;
+
+/*!
+ * \brief Decision maker function pointer
+ *
+ * \param sample the baseband I&Q sample from which to make the decision
+ *
+ * This is a function pointer that is set in the constructor to point to the
proper decision function
+ * for the specified constellation order.
+ */
+ gr_complex (gr_timing_recovery_simple_cc::*d_decision)(gr_complex sample)
const; // pointer to decision function
+
+
+
+ // Members related to symbol timing
+ float d_mu, d_gain_mu;
+ float d_omega, d_gain_omega, d_omega_rel, d_min_omega, d_max_omega;
+ gr_complex d_p_2T, d_p_1T, d_p_0T;
+ gr_complex d_c_2T, d_c_1T, d_c_0T;
+
+ /*!
+ * \brief Phase error detector function pointer
+ *
+ * \param sample the I&Q sample from which to determine the phase error
+ *
+ * This is a function pointer that is set in the constructor to point to the
proper phase error detector
+ * function for the specified constellation order.
+ */
+ float (gr_timing_recovery_simple_cc::*d_phase_error_detector)(gr_complex
sample) const;
+
+
+ //! get interpolated value
+ gri_mmse_fir_interpolator_cc *d_interp;
+
+ //! delay line length.
+ static const unsigned int DLLEN = 8;
+
+ //! delay line plus some length for overflow protection
+ gr_complex d_dl[2*DLLEN];
+
+ //! index to delay line
+ unsigned int d_dl_idx;
+
+ // FIXME: remove this once we're satisfied it all works
+ std::ofstream fout;
+
+ friend gr_timing_recovery_simple_cc_sptr
+ gr_make_timing_recovery_simple_cc (unsigned int M, float theta,
+ float alpha, float beta,
+ float fmin, float fmax,
+ float mu, float gain_mu,
+ float omega, float gain_omega, float
omega_rel);
+};
+
+#endif
Added:
gnuradio/branches/developers/trondeau/digital-wip2/gnuradio-core/src/lib/general/gr_mpsk_receiver_cc.i
===================================================================
---
gnuradio/branches/developers/trondeau/digital-wip2/gnuradio-core/src/lib/general/gr_mpsk_receiver_cc.i
(rev 0)
+++
gnuradio/branches/developers/trondeau/digital-wip2/gnuradio-core/src/lib/general/gr_mpsk_receiver_cc.i
2007-01-01 19:41:54 UTC (rev 4207)
@@ -0,0 +1,42 @@
+/* -*- c++ -*- */
+/*
+ * Copyright 2004 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 2, 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.
+ */
+
+GR_SWIG_BLOCK_MAGIC(gr,timing_recovery_simple_cc);
+
+gr_timing_recovery_simple_cc_sptr gr_make_timing_recovery_simple_cc (unsigned
int M, float theta,
+ float
alpha, float beta,
+ float
fmin, float fmax,
+ float mu,
float gain_mu,
+ float
omega, float gain_omega, float omega_rel);
+class gr_timing_recovery_simple_cc : public gr_block
+{
+ private:
+ gr_timing_recovery_simple_cc (unsigned int M,float theta,
+ float alpha, float beta,
+ float fmin, float fmax,
+ float mu, float gain_mu,
+ float omega, float gain_omega, float omega_rel);
+public:
+ unsigned int samples_per_symbol() const { return d_samples_per_symbol;}
+
+ void set_samples_per_symbol (unsigned int samples_per_symbol) {
d_samples_per_symbol = samples_per_symbol; }
+};
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