Continuous transmission FM sonar with one octave bandwidth and no blind time

  • P. T. Gough
  • A. de Roos
  • M. J. Cusdin


Despite the advantage of high average power output, traditional continuous transmission FM (CTFM) sonars suffer from two major defects: separate transmit and receive transducers are required, and the demodulated signal is unavailable for a proportion of the sweep period. The paper shows how, by using a dual-demodulation system, the demodulated signal can be made continuous, resulting in the complete elimination of the blind time and in a range resolution as good as two wavelengths of the mean frequency. Experimental results using a CTFM air sonar justify both these claims.


Spectrum Analyser Local Oscillator Range Cell Range Resolution Target Strength 
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Copyright information

© AT&T 1990

Authors and Affiliations

  • P. T. Gough
  • A. de Roos
  • M. J. Cusdin

There are no affiliations available

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