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refactor training

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This commit is contained in:
Roman Zeyde
2014-07-05 18:23:53 +03:00
parent e2bba5c298
commit 443217a51d
3 changed files with 17 additions and 16 deletions
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14
recv.py
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@@ -10,11 +10,12 @@ log = logging.getLogger(__name__)
import sigproc
import loop
import show
import train
from common import *
COHERENCE_THRESHOLD = 0.95
CARRIER_DURATION = 300
CARRIER_DURATION = sum(train.prefix)
CARRIER_THRESHOLD = int(0.95 * CARRIER_DURATION)
def detect(x, freq):
@@ -52,24 +53,23 @@ def receive(x, freqs):
symbols = iter(lp)
prefix = [1]*300 + [0]*100
S = take(symbols, carrier_index, len(prefix))
S = take(symbols, carrier_index, len(train.prefix))
y = np.abs(S)
bits = np.round(y)
bits = np.array(bits, dtype=int)
if all(bits != prefix):
if all(bits != train.prefix):
return None
log.info('Prefix OK')
err = sigproc.drift( S[np.array(prefix, dtype=bool)] ) / (Tsym * Fc)
err = sigproc.drift( S[np.array(train.prefix, dtype=bool)] ) / (Tsym * Fc)
log.info('Frequency error: %.2f ppm', err * 1e6)
lp.sampler.freq -= err
filters = {}
full_scale = len(freqs)
training_bits = np.array(([1]*10 + [0]*10)*20 + [0]*100)
training_bits = np.array(train.equalizer)
expected = full_scale * training_bits
for i, freq in enumerate(freqs):
S = take(symbols, i, len(expected))
@@ -88,7 +88,7 @@ def receive(x, freqs):
noise = y - expected
Pnoise = sigproc.power(noise)
log.debug('{:10.1f}Hz: Noise sigma={:.4f}, SNR={:.1f} dB'.format( freq, Pnoise**0.5, 10*np.log10(1/Pnoise) ))
log.debug('{:10.1f} kHz: Noise sigma={:.4f}, SNR={:.1f} dB'.format( freq/1e3, Pnoise**0.5, 10*np.log10(1/Pnoise) ))
sz = int(np.ceil(np.sqrt(len(freqs))))