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106 lines
4.0 KiB
106 lines
4.0 KiB
#!/usr/bin/env python |
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# -*- coding: utf-8 -*- |
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# |
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# Copyright 2016 <+YOU OR YOUR COMPANY+>. |
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# |
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# This is free software; you can redistribute it and/or modify |
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# it under the terms of the GNU General Public License as published by |
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# the Free Software Foundation; either version 3, or (at your option) |
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# any later version. |
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# |
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# This software is distributed in the hope that it will be useful, |
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# but WITHOUT ANY WARRANTY; without even the implied warranty of |
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# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the |
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# GNU General Public License for more details. |
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# |
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# You should have received a copy of the GNU General Public License |
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# along with this software; see the file COPYING. If not, write to |
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# the Free Software Foundation, Inc., 51 Franklin Street, |
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# Boston, MA 02110-1301, USA. |
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# |
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import numpy as np |
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from gnuradio import gr |
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import code,math,pmt |
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class max_freq(gr.sync_block): |
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""" |
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docstring for block max_freq |
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""" |
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def __init__(self, fft_len=1024,num_decoders=4,center_freq=0,samp_rate=0,round_to=100e3): |
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gr.sync_block.__init__(self, |
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name="max_freq", |
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in_sig=[(np.float32,fft_len)], |
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out_sig=None) |
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self.fft_len=fft_len |
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self.num_decoders=num_decoders |
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self.center_freq=center_freq |
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self.samp_rate=samp_rate |
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self.snapto=round_to |
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self.message_port_register_out(pmt.intern('out')) |
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def set_center_freq(self, freq=None): |
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if freq is not None: |
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if isinstance(freq, float) or isinstance(freq, int): |
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self.center_freq=freq |
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else: |
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self.center_freq = int(freq) |
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def work(self, input_items, output_items): |
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#in0 = input_items[0] |
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#ii=input_items |
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carrier_width=2 |
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carrier=self.fft_len/2 |
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numbers=np.delete(input_items[0][0],range(carrier-carrier_width,carrier+carrier_width+1))#reads input and disregards center |
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#threshold=100 uni |
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threshold=80#home |
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#minimum number of consecutive maximums (in fft domain) to consider signal as station: |
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# min_consec_max_threshold=1#uni |
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min_consec_max_threshold=5#home |
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#TODO: what if no numbers over threshold? |
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#TODO auto threshold |
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#max_indices=[[421, 428, 429, 430, 431, 432, 433, 434, 436, 437, 438, 831, 832, 837, 840, 841, 842, 843, 844, 845, 846, 847, 848, 849, 850, 851,852, 853, 854, 855, 856, 857]] |
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max_indices=np.where(numbers>threshold) |
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station_indices=[] |
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last_index=max_indices[0][0] |
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#last_index=0 |
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count=1#counts number of consecutive maximums |
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threshold_reached=False |
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#fuzzyness=2#uni |
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fuzzyness=10#home |
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# max_indices[0].append(0)#to detect last station |
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max_indices=np.append(max_indices,0)#to detect last station |
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#try: |
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#max_indices.remove(self.fft_len/2)#suppress local oscillator of hackrf |
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#except ValueError: |
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#pass |
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for i in max_indices: |
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if abs(i-last_index) <= fuzzyness: |
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count+=i-last_index |
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else:#last streak ended |
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if(threshold_reached): |
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station_indices.append(last_index-int(count/2))#use center of max-streak |
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threshold_reached=False |
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count=1 |
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else:#last streak didn't reach threshold -> no station |
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count=1 |
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if count>=min_consec_max_threshold: |
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threshold_reached=True |
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last_index=i |
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station_freqs=[] |
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#index to freq: |
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for index in station_indices: |
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startfreq=self.center_freq-self.samp_rate/2 |
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freq=self.samp_rate*index/self.fft_len+startfreq |
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num_decimals=int(round(math.log(self.snapto,10))) |
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station_freqs.append(round(freq,-num_decimals)) |
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for i in range(0,min(self.num_decoders,len(station_freqs))): |
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msg_string=str(i+1)+" "+str(station_freqs[i]) |
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send_pmt = pmt.string_to_symbol(msg_string) |
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self.message_port_pub(pmt.intern('out'), send_pmt) |
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print(max_indices) |
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print(station_indices) |
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print(station_freqs) |
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return len(input_items[0]) |
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