Class: PWN::SDR::Decoder::GSM::DemodIQ

Inherits:
Object
  • Object
show all
Defined in:
lib/pwn/sdr/decoder/gsm.rb

Overview

Streaming GMSK demod for Base.run_iq — I/Q → FCCH lock + SCH BSIC.

Instance Method Summary collapse

Constructor Details

#initialize(rate:) ⇒ DemodIQ

Returns a new instance of DemodIQ.



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# File 'lib/pwn/sdr/decoder/gsm.rb', line 29

def initialize(rate:)
  @rate  = rate.to_f
  @spb   = @rate / SYMBOL_RATE
  @audio = []
  @fcch_n = 0
  @sch_n  = 0
end

Instance Method Details

#feed_iq(samples, rate: nil) ⇒ Object 



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# File 'lib/pwn/sdr/decoder/gsm.rb', line 37

def feed_iq(samples, rate: nil, &)
  @rate = rate.to_f if rate
  @spb  = @rate / SYMBOL_RATE
  fm = PWN::SDR::Decoder::DSP.fm_demod_iq(iq: samples)
  @audio.concat(fm)
  scan(&) if block_given?
  max = (@rate * 0.25).to_i
  @audio.shift(@audio.length - max) if @audio.length > max
end