SWAC 4: Broadband Data Analysis Using Sub-Band Processing
Abstract
The frequency dependence of broadband active detection/localization is examined. The analysis is based on 1200 Hz (2300-3500 Hz) LFM signals acquired during the SWAC 4 sea trial. A sub-band matched filter scheme is devised according to which a replica of the transmitted pulse is segmented into ten 120 Hz sub-bands and processed independently through a matched filter detector. Comparison of target detection and ranging results indicate comparable performance for all sub-hands. However, ping-to-ping variability of the ten correlator outputs suggest that the detection performance may be improved by employing incoherent processing schemes. Signal-to-noise ratio is proved to be controlled mainly by noise (reverberation is the predominant noise source) rather than signal variations. The signal intensity remains proportional to the distance between source and receiver due to favorable propagation conditions. Doppler effects and sub-band detection synchronization problems which may lead to performance degradation in large time-bandwidth signal processing are addressed. A method to estimate range rate (relative velocity between source and receiver) based on single ping differential time delay between sub-band MF outputs is developed. This intra-ping technique is an alternative to the standard inter-ping method which requires multiping detection history.
Document Details
- Document Type
- Technical Report
- Publication Date
- Jan 01, 2000
- Accession Number
- ADA378129
Entities
People
- E. Capriulo
- G. Haralabus
- W. M. Zimmer
Organizations
- SACLANT ASW Research Centre