From 0a4225dc9dd9e4d3c5ad58d40570d40d59f5670f Mon Sep 17 00:00:00 2001
From: David Pi <david.pinho@gmail.com>
Date: Sat, 17 Jul 2021 13:25:03 +0100
Subject: gr-digital: Fix constellation normalization by average power
Correct power normalization calculation.
Add a qa test for amplitude and power normalization.
Signed-off-by: David Pi <david.pinho@gmail.com>
---
gr-digital/python/digital/qa_constellation.py | 23 ++++++++++++++++++++++-
1 file changed, 22 insertions(+), 1 deletion(-)
(limited to 'gr-digital/python/digital/qa_constellation.py')
diff --git a/gr-digital/python/digital/qa_constellation.py b/gr-digital/python/digital/qa_constellation.py
index d13dae376e..7c9984405f 100644
--- a/gr-digital/python/digital/qa_constellation.py
+++ b/gr-digital/python/digital/qa_constellation.py
@@ -16,7 +16,8 @@ import numpy
from gnuradio import gr, gr_unittest, digital, blocks
from gnuradio.digital.utils import mod_codes
-from gnuradio.digital import psk, qam, qamlike
+from gnuradio.digital import constellation, psk, qam, qamlike
+import numpy as np
tested_mod_codes = (mod_codes.NO_CODE, mod_codes.GRAY_CODE)
@@ -178,6 +179,26 @@ class test_constellation(gr_unittest.TestCase):
def tearDown(self):
pass
+ def test_normalization(self):
+ rot_sym = 1
+ side = 2
+ width = 2
+ # Test a couple of basic constellations
+ for constel_points, code in (digital.psk_4_0(), digital.qam_16_0()):
+ constel = digital.constellation_rect(constel_points, code, rot_sym,
+ side, side, width, width,
+ constellation.POWER_NORMALIZATION)
+
+ points = np.array(constel.points())
+ avg_power = np.sum(abs(points)**2) / len(points)
+ self.assertAlmostEqual(avg_power, 1.0, 6)
+ constel = digital.constellation_rect(constel_points, code, rot_sym,
+ side, side, width, width,
+ constellation.AMPLITUDE_NORMALIZATION)
+ points = np.array(constel.points())
+ avg_amp = np.sum(abs(points)) / len(points)
+ self.assertAlmostEqual(avg_amp, 1.0, 6)
+
def test_hard_decision(self):
for constellation, differential in tested_constellations():
if differential:
--
cgit v1.2.3