diff options
| -rw-r--r-- | gnuradio-core/src/python/gnuradio/blks2impl/ofdm_sync_ml.py | 36 |
1 files changed, 25 insertions, 11 deletions
diff --git a/gnuradio-core/src/python/gnuradio/blks2impl/ofdm_sync_ml.py b/gnuradio-core/src/python/gnuradio/blks2impl/ofdm_sync_ml.py index 59c4913d1..7c75d7f1d 100644 --- a/gnuradio-core/src/python/gnuradio/blks2impl/ofdm_sync_ml.py +++ b/gnuradio-core/src/python/gnuradio/blks2impl/ofdm_sync_ml.py @@ -98,7 +98,7 @@ class ofdm_sync_ml(gr.hier_block2): self.connect(self.diff, self.pk_detect) # The DPLL corrects for timing differences between CP correlations - use_dpll = 1 + use_dpll = 0 if use_dpll: self.dpll = gr.dpll_bb(float(symbol_length),0.01) self.connect(self.pk_detect, self.dpll) @@ -117,21 +117,29 @@ class ofdm_sync_ml(gr.hier_block2): kstime.reverse() self.kscorr = gr.fir_filter_ccc(1, kstime) self.corrmag = gr.complex_to_mag_squared() + self.div = gr.divide_ff() # The output signature of the correlation has a few spikes because the rest of the # system uses the repeated preamble symbol. It needs to work that generically if - # anyone wants to use this against a WiMAX-like signal since it, too, repeats - # This slicing against a threshold will __not__ work over the air unless the - # received power is at just the right point. It __does__ work under the normal - # conditions of the loopback model. - self.slice = gr.threshold_ff(700000, 700000, 0) + # anyone wants to use this against a WiMAX-like signal since it, too, repeats. + # The output theta of the correlator above is multiplied with this correlation to + # identify the proper peak and remove other products in this cross-correlation + self.threshold_factor = 0.1 + self.slice = gr.threshold_ff(self.threshold_factor, self.threshold_factor, 0) self.f2b = gr.float_to_char() + self.b2f = gr.char_to_float() + self.mul = gr.multiply_ff() + + # Normalize the power of the corr output by the energy. This is not really needed + # and could be removed for performance, but it makes for a cleaner signal. + # if this is removed, the threshold value needs adjustment. + self.connect(self.input, self.kscorr, self.corrmag, (self.div,0)) + self.connect(self.moving_sum_filter, (self.div,1)) + + self.connect(self.div, (self.mul,0)) + self.connect(self.pk_detect, self.b2f, (self.mul,1)) + self.connect(self.mul, self.slice) - self.connect(self.input, self.kscorr, self.corrmag, self.slice) - self.connect(self.kscorr, gr.file_sink(gr.sizeof_gr_complex, "kscorr.dat")) - self.connect(self.corrmag, gr.file_sink(gr.sizeof_float, "kscorrmag.dat")) - self.connect(self.slice, gr.file_sink(gr.sizeof_float, "kspeak.dat")) - # Set output signals # Output 0: fine frequency correction value # Output 1: timing signal @@ -140,8 +148,14 @@ class ofdm_sync_ml(gr.hier_block2): if logging: + self.connect(self.moving_sum_filter, gr.file_sink(gr.sizeof_float, "ofdm_sync_ml-energy_f.dat")) self.connect(self.diff, gr.file_sink(gr.sizeof_float, "ofdm_sync_ml-theta_f.dat")) self.connect(self.angle, gr.file_sink(gr.sizeof_float, "ofdm_sync_ml-epsilon_f.dat")) + self.connect(self.corrmag, gr.file_sink(gr.sizeof_float, "ofdm_sync_ml-corrmag_f.dat")) + self.connect(self.kscorr, gr.file_sink(gr.sizeof_gr_complex, "ofdm_sync_ml-kscorr_c.dat")) + self.connect(self.div, gr.file_sink(gr.sizeof_float, "ofdm_sync_ml-div_f.dat")) + self.connect(self.mul, gr.file_sink(gr.sizeof_float, "ofdm_sync_ml-mul_f.dat")) + self.connect(self.slice, gr.file_sink(gr.sizeof_float, "ofdm_sync_ml-slice_f.dat")) self.connect(self.pk_detect, gr.file_sink(gr.sizeof_char, "ofdm_sync_ml-peaks_b.dat")) if use_dpll: self.connect(self.dpll, gr.file_sink(gr.sizeof_char, "ofdm_sync_ml-dpll_b.dat")) |