diff options
| author | Tom Rondeau <tom@trondeau.com> | 2013-09-04 15:44:20 -0400 |
|---|---|---|
| committer | Tom Rondeau <tom@trondeau.com> | 2013-09-04 15:44:20 -0400 |
| commit | 02fd90029a1ec465f7c8da4a0d97dcdb8b3f438f (patch) | |
| tree | 9bc144a9cb5b0e877108302d13181e50bd885528 /gr-digital/python/digital/qa_constellation.py | |
| parent | edf2ac24c9c2f723eb80918de7addf6d299958c2 (diff) | |
digital: Python functions to support soft decision making and look-up table generation.
Diffstat (limited to 'gr-digital/python/digital/qa_constellation.py')
| -rw-r--r-- | gr-digital/python/digital/qa_constellation.py | 82 |
1 files changed, 81 insertions, 1 deletions
diff --git a/gr-digital/python/digital/qa_constellation.py b/gr-digital/python/digital/qa_constellation.py index 83a875af4b..00248f4f09 100644 --- a/gr-digital/python/digital/qa_constellation.py +++ b/gr-digital/python/digital/qa_constellation.py @@ -21,7 +21,7 @@ # import random -from cmath import exp, pi, log +from cmath import exp, pi, log, sqrt from gnuradio import gr, gr_unittest, digital, blocks from gnuradio.digital.utils import mod_codes @@ -185,6 +185,86 @@ class test_constellation(gr_unittest.TestCase): first = constellation.bits_per_symbol() self.assertEqual(self.src_data[first:len(data)], data[first:]) + def test_soft_qpsk_gen(self): + prec = 8 + constel, code = digital.psk_4_0() + + rot_sym = 1 + side = 2 + width = 2 + c = digital.constellation_rect(constel, code, rot_sym, + side, side, width, width) + + # Get max energy/symbol in constellation + constel = c.points() + Es = max([abs(constel_i) for constel_i in constel]) + + table = digital.soft_dec_table_generator(digital.sd_psk_4_0, prec, Es) + c.set_soft_dec_lut(table, prec) + + x = sqrt(2.0)/2.0 + step = (x.real+x.real) / (2**prec - 1) + samples = [ -x-x*1j, -x+x*1j, + x+x*1j, x-x*1j, + (-x+128*step)+(-x+128*step)*1j, + (-x+64*step) +(-x+64*step)*1j, (-x+64*step) +(-x+192*step)*1j, + (-x+192*step)+(-x+192*step)*1j, (-x+192*step)+(-x+64*step)*1j,] + + y_python_raw_calc = [] + y_python_gen_calc = [] + y_python_table = [] + y_cpp_raw_calc = [] + y_cpp_table = [] + for sample in samples: + y_python_raw_calc += digital.calc_soft_dec(sample, constel, code) + y_python_gen_calc += digital.sd_psk_4_0(sample, Es) + y_python_table += digital.calc_soft_dec_from_table(sample, table, prec, Es) + + y_cpp_raw_calc += c.calc_soft_dec(sample) + y_cpp_table += c.soft_decision_maker(sample) + + self.assertFloatTuplesAlmostEqual(y_python_raw_calc, y_python_gen_calc, 4) + self.assertFloatTuplesAlmostEqual(y_python_raw_calc, y_python_table, 2) + self.assertFloatTuplesAlmostEqual(y_cpp_raw_calc, y_cpp_table, 4) + + def test_soft_qpsk_calc(self): + prec = 8 + constel, code = digital.psk_4_0() + + rot_sym = 1 + side = 2 + width = 2 + c = digital.constellation_rect(constel, code, rot_sym, + side, side, width, width) + + # Get max energy/symbol in constellation + constel = c.points() + Es = max([abs(constel_i) for constel_i in constel]) + + table = digital.soft_dec_table(constel, code, prec) + c.gen_soft_dec_lut(prec) + + x = sqrt(2.0)/2.0 + step = (x.real+x.real) / (2**prec - 1) + samples = [ -x-x*1j, -x+x*1j, + x+x*1j, x-x*1j, + (-x+128*step)+(-x+128*step)*1j, + (-x+64*step) +(-x+64*step)*1j, (-x+64*step) +(-x+192*step)*1j, + (-x+192*step)+(-x+192*step)*1j, (-x+192*step)+(-x+64*step)*1j,] + + y_python_raw_calc = [] + y_python_table = [] + y_cpp_raw_calc = [] + y_cpp_table = [] + for sample in samples: + y_python_raw_calc += digital.calc_soft_dec(sample, constel, code) + y_python_table += digital.calc_soft_dec_from_table(sample, table, prec, Es) + + y_cpp_raw_calc += c.calc_soft_dec(sample) + y_cpp_table += c.soft_decision_maker(sample) + + self.assertFloatTuplesAlmostEqual(y_python_raw_calc, y_python_table, 4) + self.assertFloatTuplesAlmostEqual(y_cpp_raw_calc, y_cpp_table, 4) class mod_demod(gr.hier_block2): def __init__(self, constellation, differential, rotation): |