diff options
Diffstat (limited to 'gr-uhd/apps/hf_radio/ssbagc.py')
| -rw-r--r-- | gr-uhd/apps/hf_radio/ssbagc.py | 48 |
1 files changed, 48 insertions, 0 deletions
diff --git a/gr-uhd/apps/hf_radio/ssbagc.py b/gr-uhd/apps/hf_radio/ssbagc.py new file mode 100644 index 000000000..fdf40bc6b --- /dev/null +++ b/gr-uhd/apps/hf_radio/ssbagc.py @@ -0,0 +1,48 @@ +# post detection agc processing +# +# Imagine that the usual gnuradio copyright stuff is right here. +# +# This agc strategy is copied more or less verbatim from +# weaver_isb_am1_usrp3.py by cswiger. +# +# Thanks. +# +# Then modified in a variety of ways. +# +# There doesn't appear to be a way to hook multiple blocks to the +# input port when building a hier block like this. Thus the +# split below. +# +# Basic operation. +# Power is estimated by squaring the input. +# Low pass filter using a 1 pole iir. +# The time constant can be tweaked by changing the taps. +# Currently there is no implementation to change this while operating +# a potentially useful addition. +# The log block turns this into dB +# gain adjusts the agc authority. +# +# M. Revnell 2006-Jan + +from gnuradio import gr, gru + +class agc( gr.hier_block ): + def __init__( self, fg ): + self.split = gr.multiply_const_ff( 1 ) + self.sqr = gr.multiply_ff( ) + self.int0 = gr.iir_filter_ffd( [.004, 0], [0, .999] ) + self.offs = gr.add_const_ff( -30 ) + self.gain = gr.multiply_const_ff( 70 ) + self.log = gr.nlog10_ff( 10, 1 ) + self.agc = gr.divide_ff( ) + + fg.connect( self.split, ( self.agc, 0 ) ) + fg.connect( self.split, ( self.sqr, 0 ) ) + fg.connect( self.split, ( self.sqr, 1 ) ) + fg.connect( self.sqr, self.int0 ) + fg.connect( self.int0, self.log ) + fg.connect( self.log, self.offs ) + fg.connect( self.offs, self.gain ) + fg.connect( self.gain, ( self.agc, 1 ) ) + + gr.hier_block.__init__( self, fg, self.split, self.agc ) |