Files
amodem/tests/test_qam.py
2014-09-19 09:24:42 +03:00

40 lines
968 B
Python

import random
import itertools
import numpy as np
from amodem import qam
from amodem import config
def test_qam():
q = qam.QAM(config.symbols)
r = random.Random(0)
m = q.bits_per_symbol
bits = [tuple(r.randint(0, 1) for j in range(m)) for i in range(1024)]
stream = itertools.chain(*bits)
S = list(q.encode(list(stream)))
decoded = list(q.decode(S))
assert decoded == bits
noise = lambda A: A*(r.uniform(-1, 1) + 1j*r.uniform(-1, 1))
noised_symbols = [(s + noise(1e-3)) for s in S]
decoded = list(q.decode(noised_symbols))
assert decoded == bits
def quantize(q, s):
bits, = list(q.decode([s]))
r, = q.encode(bits)
index = np.argmin(np.abs(s - q.symbols))
expected = q.symbols[index]
assert r == expected
def test_overflow():
q = qam.QAM(config.symbols)
r = np.random.RandomState(seed=0)
for i in range(10000):
s = 10*(r.normal() + 1j * r.normal())
quantize(q, s)