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refactor loop

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This commit is contained in:
Roman Zeyde
2014-07-05 09:39:57 +03:00
parent c1302a2d82
commit c9d7f8e2f2
2 changed files with 21 additions and 44 deletions
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25
drift.py
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@@ -1,31 +1,10 @@
import numpy as np import numpy as np
import pylab
import recv
import common import common
import sigproc import sigproc
import sampling
import loop import loop
class FreqLoop(object):
def __init__(self, x, freq):
self.sampler = sampling.Sampler(x, sampling.Interpolator())
self.symbols = recv.extract_symbols(self.sampler, freq)
Kp, Ki = 0.2, 0.01
b = np.array([1, -1])*Kp + np.array([0.5, 0.5])*Ki
self.filt = loop.Filter(b=b, a=[1])
self.correction = 0.0
def correct(self, actual, expected):
self.err = np.angle(expected / actual) / np.pi
self.err = sigproc.clip(self.err, [-0.1, 0.1])
self.correction = self.filt(self.err)
self.sampler.correct(offset=self.correction)
def __iter__(self):
return iter(self.symbols)
import pylab
def main(): def main():
f0 = 10e3 f0 = 10e3
_, x = common.load(file('recv_10kHz.pcm', 'rb')) _, x = common.load(file('recv_10kHz.pcm', 'rb'))
@@ -34,7 +13,7 @@ def main():
S = [] S = []
Y = [] Y = []
symbols = FreqLoop(x, f0) symbols = loop.FreqLoop(x, f0)
prefix = 100 prefix = 100
for s in symbols: for s in symbols:
S.append(s) S.append(s)

40
loop.py
View File

@@ -1,5 +1,9 @@
import numpy as np import numpy as np
import recv
import sampling
import sigproc
class Filter(object): class Filter(object):
def __init__(self, b, a=()): def __init__(self, b, a=()):
self.b = b self.b = b
@@ -15,26 +19,20 @@ class Filter(object):
self.y = [y] + self.y self.y = [y] + self.y
return y return y
class Loop(object): class FreqLoop(object):
def __init__(self, x, A, k, h): def __init__(self, x, freq):
self.x = np.array(x) self.sampler = sampling.Sampler(x, sampling.Interpolator())
self.A = np.array(A) self.symbols = recv.extract_symbols(self.sampler, freq)
self.k = np.array(k) Kp, Ki = 0.2, 0.01
self.h = np.array(h) b = np.array([1, -1])*Kp + np.array([0.5, 0.5])*Ki
self.filt = Filter(b=b, a=[1])
self.correction = 0.0
def __call__(self, y): def correct(self, actual, expected):
self.err = y - np.dot(self.h, self.x) self.err = np.angle(expected / actual) / np.pi
self.dx = self.k * self.err self.err = sigproc.clip(self.err, [-0.1, 0.1])
self.x = self.x + self.dx self.correction = self.filt(self.err)
self.x = np.dot(self.A, self.x) self.sampler.correct(offset=self.correction)
class Integrator(Loop):
def __init__(self, phase, freq, k):
x = [phase, freq] # state variable vector
# evolution matrix:
# | phase' = phase + freq
# | freq' = freq
A = [[1, 1], [0, 1]]
h = [1, 0] # phase = dot(h, x)
Loop.__init__(self, x=x, A=A, k=k, h=h)
def __iter__(self):
return iter(self.symbols)