diff options
| -rw-r--r-- | tests/correlator/correlator.grc | 65 | ||||
| -rwxr-xr-x | tests/correlator/correlator.py | 2 | ||||
| -rw-r--r-- | tests/correlator/epy_block_0.py | 75 |
3 files changed, 91 insertions, 51 deletions
diff --git a/tests/correlator/correlator.grc b/tests/correlator/correlator.grc index aa21770..58cf3b4 100644 --- a/tests/correlator/correlator.grc +++ b/tests/correlator/correlator.grc @@ -408,7 +408,7 @@ blocks: block_tags: 'False' comment: '' epsilon: '1.0' - freq_offset: '0.00001' + freq_offset: '0.0001' maxoutbuf: '0' minoutbuf: '0' noise_voltage: '0.2' @@ -530,30 +530,45 @@ blocks: \ many samples were processed,\n # because tags have an absolute offset\n\ \ self.sampnr: np.complex64 = 0\n\n # because of block processing\ \ a tagged block could\n # be split in half so we need to keep track\ - \ of the\n # \"previous\" values\n self.last_phase = 0\n\n \ - \ def work(self, input_items, output_items):\n # TODO: interpolate phase\ - \ values for frequency correction\n\n out = output_items[0]\n \ - \ inp = input_items[0]\n\n # create a phase correction vector\n \ - \ phase = np.zeros(len(inp), dtype=np.float64)\n\n # read tags\n \ - \ tags = self.get_tags_in_window(0, 0, len(inp))\n\n # get only\ - \ phase tags\n is_phase = lambda tag: pmt.to_python(tag.key) == \"phase_est\"\ - \n phase_tags = list(filter(is_phase, tags))\n\n print(f\"Processing\ - \ {len(inp)} samples, with {len(phase_tags)} tags\")\n\n # compute correction\ - \ from previous block\n first_tag = phase_tags[0]\n first_idx\ - \ = first_tag.offset - self.sampnr\n phase[:first_idx] = self.last_phase\n\ - \n # iterate phase tags \"in the middle\"\n for prev_tag, next_tag\ - \ in zip(phase_tags, phase_tags[1:]):\n # unpack pmt values\n \ - \ pval = pmt.to_python(prev_tag.value)\n\n # compute indexes\ + \ of the\n # \"previous\" values\n self.last_tag = None\n\n \ + \ def work(self, input_items, output_items):\n # nicer aliases\n \ + \ out = output_items[0]\n inp = input_items[0]\n\n def print_phase_correction(start,\ + \ end, phase, freq):\n print(f\"Correction for block {start:3d} to\ + \ {end:3d} is phase = {phase: 2.4f} rad, freq = {freq * 1e3: 2.4f} milli rad/samp\"\ + )\n\n # read only phase tags\n tags = self.get_tags_in_window(0,\ + \ 0, len(inp))\n\n is_phase = lambda tag: pmt.to_python(tag.key) == \"\ + phase_est\"\n phase_tags = list(filter(is_phase, tags))\n\n #\ + \ FIXME: what if there are no tags? check that!\n\n print(f\"Processing\ + \ {len(inp)} samples, with {len(phase_tags)} tags\")\n\n # create a phase\ + \ correction vector\n phase = np.zeros(len(inp), dtype=np.float64)\n\n\ + \ # compute correction from previous block (if present)\n if self.last_tag:\n\ + \ # variables for first and last phase values\n lval =\ + \ pmt.to_python(self.last_tag.value)\n fval = pmt.to_python(phase_tags[0].value)\n\ + \n # compute index for phase vector\n fidx = phase_tags[0].offset\ + \ - self.sampnr\n\n # compute frequency offset\n nsamples\ + \ = phase_tags[0].offset - self.last_tag.offset\n freq = (fval -\ + \ lval) / nsamples\n\n # total phase correction is: phase + freq\ + \ * time\n phase[:fidx] = lval * np.ones(fidx) + freq * np.arange(0,\ + \ fidx)\n\n # compute correction\n print_phase_correction(0,\ + \ fidx, lval, freq)\n\n # iterate phase tags \"in the middle\"\n \ + \ # FIXME: what if there are less than 2 tags?\n # the code\ + \ below will probably crash\n for prev_tag, next_tag in zip(phase_tags,\ + \ phase_tags[1:]):\n # unpack pmt values\n pval = pmt.to_python(prev_tag.value)\n\ + \ nval = pmt.to_python(next_tag.value)\n\n # compute indexes\ \ in phase vector\n pidx = prev_tag.offset - self.sampnr\n \ - \ idx = next_tag.offset - self.sampnr\n\n # compute phase correction\ - \ for block\n phase[pidx:idx] = pval\n print(f\"Correction\ - \ for block {pidx} to {idx} is {pval}\")\n\n # compute the remaining\ - \ part of the block\n last_tag = phase_tags[-1]\n last_val = pmt.to_python(last_tag.value)\n\ - \ last_idx = last_tag.offset - self.sampnr\n\n phase[last_idx:]\ - \ = last_val\n\n # save values for next call\n self.last_phase\ - \ = last_val\n\n # mark samples as processed and compute to output\n\ - \ self.sampnr += len(inp)\n out[:] = inp * np.exp(-1j * phase)\n\ - \n return len(out)\n" + \ nidx = next_tag.offset - self.sampnr\n\n # compute frquency\ + \ correction for block by linearly interpolating\n # frame values\n\ + \ nsamples = nidx - pidx\n freq = (nval - pval) / nsamples\n\ + \n # total correction is: phase + freq * time\n phase[pidx:nidx]\ + \ = pval * np.ones(nsamples) + freq * np.arange(0, nsamples)\n print_phase_correction(pidx,\ + \ nidx, pval, freq)\n\n # for the last block because the next tag is\ + \ unknown (in the future) we\n # cannot predict the frequency offset.\ + \ Thus we save the last tag for\n # the next call.\n self.last_tag\ + \ = phase_tags[-1]\n val = pmt.to_python(self.last_tag.value)\n \ + \ idx = self.last_tag.offset - self.sampnr\n\n phase[idx:] = val\n\n\ + \ # compute correction\n out[:] = inp * np.exp(-1j * phase)\n\n\ + \ # increment processed samples counter\n self.sampnr += len(inp)\n\ + \ return len(phase)\n" affinity: '' alias: '' comment: '' @@ -583,7 +598,7 @@ blocks: bus_structure: null coordinate: [552, 1388.0] rotation: 0 - state: true + state: bypassed - name: fir_filter_xxx_1 id: fir_filter_xxx parameters: diff --git a/tests/correlator/correlator.py b/tests/correlator/correlator.py index 67def9f..93ee8bb 100755 --- a/tests/correlator/correlator.py +++ b/tests/correlator/correlator.py @@ -345,7 +345,7 @@ class correlator(gr.top_block, Qt.QWidget): self.digital_cma_equalizer_cc_0 = digital.cma_equalizer_cc(15, 1, .002, 1) self.channels_channel_model_0 = channels.channel_model( noise_voltage=0.2, - frequency_offset=0.00001, + frequency_offset=0.0001, epsilon=1.0, taps=[-1.4 + .4j], noise_seed=243, diff --git a/tests/correlator/epy_block_0.py b/tests/correlator/epy_block_0.py index 1fa4794..90ad75e 100644 --- a/tests/correlator/epy_block_0.py +++ b/tests/correlator/epy_block_0.py @@ -20,56 +20,81 @@ class blk(gr.sync_block): # because of block processing a tagged block could # be split in half so we need to keep track of the # "previous" values - self.last_phase = 0 + self.last_tag = None def work(self, input_items, output_items): - # TODO: interpolate phase values for frequency correction - + # nicer aliases out = output_items[0] inp = input_items[0] - # create a phase correction vector - phase = np.zeros(len(inp), dtype=np.float64) + def print_phase_correction(start, end, phase, freq): + print(f"Correction for block {start:3d} to {end:3d} is phase = {phase: 2.4f} rad, freq = {freq * 1e3: 2.4f} milli rad/samp") - # read tags + # read only phase tags tags = self.get_tags_in_window(0, 0, len(inp)) - # get only phase tags is_phase = lambda tag: pmt.to_python(tag.key) == "phase_est" phase_tags = list(filter(is_phase, tags)) + # FIXME: what if there are no tags? check that! + print(f"Processing {len(inp)} samples, with {len(phase_tags)} tags") - # compute correction from previous block - first_tag = phase_tags[0] - first_idx = first_tag.offset - self.sampnr - phase[:first_idx] = self.last_phase + # create a phase correction vector + phase = np.zeros(len(inp), dtype=np.float64) + + # compute correction from previous block (if present) + if self.last_tag: + # variables for first and last phase values + lval = pmt.to_python(self.last_tag.value) + fval = pmt.to_python(phase_tags[0].value) + + # compute index for phase vector + fidx = phase_tags[0].offset - self.sampnr + + # compute frequency offset + nsamples = phase_tags[0].offset - self.last_tag.offset + freq = (fval - lval) / nsamples + + # total phase correction is: phase + freq * time + phase[:fidx] = lval * np.ones(fidx) + freq * np.arange(0, fidx) + + # compute correction + print_phase_correction(0, fidx, lval, freq) # iterate phase tags "in the middle" + # FIXME: what if there are less than 2 tags? + # the code below will probably crash for prev_tag, next_tag in zip(phase_tags, phase_tags[1:]): # unpack pmt values pval = pmt.to_python(prev_tag.value) + nval = pmt.to_python(next_tag.value) # compute indexes in phase vector pidx = prev_tag.offset - self.sampnr - idx = next_tag.offset - self.sampnr + nidx = next_tag.offset - self.sampnr - # compute phase correction for block - phase[pidx:idx] = pval - print(f"Correction for block {pidx} to {idx} is {pval}") + # compute frquency correction for block by linearly interpolating + # frame values + nsamples = nidx - pidx + freq = (nval - pval) / nsamples - # compute the remaining part of the block - last_tag = phase_tags[-1] - last_val = pmt.to_python(last_tag.value) - last_idx = last_tag.offset - self.sampnr + # total correction is: phase + freq * time + phase[pidx:nidx] = pval * np.ones(nsamples) + freq * np.arange(0, nsamples) + print_phase_correction(pidx, nidx, pval, freq) - phase[last_idx:] = last_val + # for the last block because the next tag is unknown (in the future) we + # cannot predict the frequency offset. Thus we save the last tag for + # the next call. + self.last_tag = phase_tags[-1] + val = pmt.to_python(self.last_tag.value) + idx = self.last_tag.offset - self.sampnr - # save values for next call - self.last_phase = last_val + phase[idx:] = val - # mark samples as processed and compute to output - self.sampnr += len(inp) + # compute correction out[:] = inp * np.exp(-1j * phase) - return len(out) + # increment processed samples counter + self.sampnr += len(inp) + return len(phase) |