Sonar imagery of mobile targets
Abstract
A spectral autoregression model is presented for extracting imagery from the brilliant reflections of pure tone sonar signals reflected from a moving target. The model is intended for bypassing the resolution degradation normally caused by temporal and frequency shifts. The Doppler shift caused by a large, moving object (100 m long) is shown to be large enough at a 1000 m distance with a 30 kHz signal that sequential autospectral analysis of the shifts can provide transverse image data of the target. A Fourier transformation would be inadequate for characterizing the difference in the return signals. The autoregression analysis proceeds by pattern recognition and error prediction steps at a set time interval. A SNR of 20 dB is obtained, which exceeds that available using PCM techniques.
- Publication:
-
ONERA
- Pub Date:
- 1985
- Bibcode:
- 1985tsa..coll.....M
- Keywords:
-
- Moving Target Indicators;
- Signal Analysis;
- Sonar;
- Spectrum Analysis;
- Autoregressive Processes;
- Doppler Effect;
- Fourier Analysis;
- Signal Processing;
- Signal To Noise Ratios;
- Communications and Radar