Python gnuradio.filter.fir_filter_ccf() Examples

def __init__(self):
    gr.top_block.__init__(self, name="Doorbell Top Block")

    # RF Config
    self.threshold_min = -60
    self.threshold_max = -50
    self.samp_rate = samp_rate = 100e3
    self.gain = gain = 30
    self.freq = freq = 315e6
    self.decimation = 10

    # USRP
    self.usrp = uhd.usrp_source("", uhd.stream_args("fc32"))
    self.usrp.set_samp_rate(samp_rate)
    self.usrp.set_center_freq(freq, 0)
    self.usrp.set_gain(gain, 0)
    self.usrp.set_antenna("TX/RX", 0)

    # Low Pass Filter
    self.lpf = filter.fir_filter_ccf(self.decimation,
      firdes.low_pass(1, samp_rate, 50e3, 10e3, firdes.WIN_HAMMING, 6.76))

    # Complex to Power (dB)
    self._10log10 = blocks.nlog10_ff(10, 1, 0)
    self.complex_to_mag_squared = blocks.complex_to_mag_squared(1)

    # Threshold
    self.threshold = blocks.threshold_ff(self.threshold_min, self.threshold_max, 0)

    # Framer
    self.framer = doorbell_framer()

    # Connect the blocks
    self.connect((self.usrp, 0), (self.lpf, 0))
    self.connect((self.lpf, 0), (self.complex_to_mag_squared, 0))
    self.connect((self.complex_to_mag_squared, 0), (self._10log10, 0))
    self.connect((self._10log10, 0), (self.threshold, 0))
    self.connect((self.threshold, 0), (self.framer, 0))


# Doorbell Framer 

def __init__(self):
        gr.top_block.__init__(self, "Top Block")

        ##################################################
        # Variables
        ##################################################
        self.trans_width = trans_width = 10e3
        self.samp_rate = samp_rate = 1e6
        self.mult_const = mult_const = 100
        self.lowpass_decimation = lowpass_decimation = 10
        self.freq = freq = 344940000
        self.cutoff_freq = cutoff_freq = 50e3

        ##################################################
        # Blocks
        ##################################################
        self.osmosdr_source_0 = osmosdr.source( args="numchan=" + str(1) + " " + '' )
        self.osmosdr_source_0.set_sample_rate(samp_rate)
        self.osmosdr_source_0.set_center_freq(freq, 0)
        self.osmosdr_source_0.set_freq_corr(0, 0)
        self.osmosdr_source_0.set_dc_offset_mode(0, 0)
        self.osmosdr_source_0.set_iq_balance_mode(0, 0)
        self.osmosdr_source_0.set_gain_mode(True, 0)
        self.osmosdr_source_0.set_gain(0, 0)
        self.osmosdr_source_0.set_if_gain(20, 0)
        self.osmosdr_source_0.set_bb_gain(20, 0)
        self.osmosdr_source_0.set_antenna('', 0)
        self.osmosdr_source_0.set_bandwidth(0, 0)
          
        self.low_pass_filter_0 = filter.fir_filter_ccf(lowpass_decimation, firdes.low_pass(
        	1, samp_rate, cutoff_freq, trans_width, firdes.WIN_HAMMING, 6.76))
        self.blocks_multiply_const_vxx_0 = blocks.multiply_const_vff((mult_const, ))
        self.blocks_float_to_uchar_0 = blocks.float_to_uchar()
        self.blocks_file_sink_1 = blocks.file_sink(gr.sizeof_char*1, '/tmp/grcfifo', False)
        self.blocks_file_sink_1.set_unbuffered(False)
        self.blocks_complex_to_mag_0 = blocks.complex_to_mag(1)

        ##################################################
        # Connections
        ##################################################
        self.connect((self.blocks_complex_to_mag_0, 0), (self.blocks_multiply_const_vxx_0, 0))    
        self.connect((self.blocks_float_to_uchar_0, 0), (self.blocks_file_sink_1, 0))    
        self.connect((self.blocks_multiply_const_vxx_0, 0), (self.blocks_float_to_uchar_0, 0))    
        self.connect((self.low_pass_filter_0, 0), (self.blocks_complex_to_mag_0, 0))    
        self.connect((self.osmosdr_source_0, 0), (self.low_pass_filter_0, 0)) 

def rebuild_filters(self,config,value = None):
    if self.cw_base == None:
      return
    if value == None:
      value = config['bw_mode']
      
    am_bw = (8000,3000,2000)[value]
    fm_bw = (8000,6000,4000)[value]
    wfm_bw = (60e3,40e3,20e3)[value]
    ssb_bw = (5000,2400,1800)[value]
    cw_bw = (self.cw_base*2/3,self.cw_base/2,self.cw_base/3)[value]
    
    am_taps = firdes.low_pass(
      1, self.audio_rate, am_bw, 500, firdes.WIN_HAMMING, 6.76)
    fm_taps = firdes.low_pass(
      1, self.audio_rate, fm_bw, 500, firdes.WIN_HAMMING, 6.76)
    wfm_taps = firdes.low_pass(
      1, self.if_sample_rate, wfm_bw, 4e3, firdes.WIN_HAMMING, 6.76)
    ssb_taps = firdes.low_pass(
      1, self.audio_rate, ssb_bw, 100, firdes.WIN_HAMMING, 6.76)
    #print("CW Base: %d - %d - %d" % (self.cw_base-cw_bw,self.cw_base + cw_bw,self.audio_rate))
    cw_taps = firdes.band_pass(
      1, self.audio_rate, self.cw_base-cw_bw,self.cw_base+cw_bw, 100, firdes.WIN_HAMMING, 6.76)
    
    if self.low_pass_filter_am == None:
      self.low_pass_filter_am = filter.fir_filter_ccf(1, am_taps)
    else:
      self.low_pass_filter_am.set_taps(am_taps) 
      
    if self.low_pass_filter_fm == None:
      self.low_pass_filter_fm = filter.fir_filter_ccf(1, fm_taps)
    else:
      self.low_pass_filter_fm.set_taps(fm_taps)
      
    if self.low_pass_filter_wfm == None:
      self.low_pass_filter_wfm = filter.fir_filter_ccf(1, wfm_taps)
    else:
      self.low_pass_filter_wfm.set_taps(wfm_taps)
      
    if self.low_pass_filter_ssb == None:
      self.low_pass_filter_ssb = filter.fir_filter_fff(1, ssb_taps)
    else:
      self.low_pass_filter_ssb.set_taps(ssb_taps)
      
    if self.band_pass_filter_cw == None:
      self.band_pass_filter_cw = filter.fir_filter_fff(1, cw_taps)
    else:
      self.band_pass_filter_cw.set_taps(cw_taps)
      
  # calculate gcd using Euclid's algorithm