DETECTION OF PPM ACOUSTIC PULSE IN SHALLOW SEA CHANNELS

来源 :Chinese Journal of Oceanology and Limnology | 被引量 : 0次 | 上传用户:hzau1
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Pulse pesition modulated (PPM) acoustic pulses are difficult to detect exacily in shallow sea channels because of strong multipath interference, large signal fluctuation and high noise level.This paper reports results of analysis on the main characteristics of multipath interference and its adverse effects on detection of pulse position information. Feasible methods to overeome multipath interference are pointed out, and an efficient one is proposed to realize reliable and precise detection of PPM information.The results of this study are of reference value for other modes of signal detection. Pulse pesition modulated (PPM) acoustic pulses are difficult to detect exacily in shallow sea channels because of strong multipath interference, large signal fluctuation and high noise level. This paper reports results of analysis on the main characteristics of multipath interference and its adverse effects on detection of pulse position information. Feasible methods to overeome multipath interference are pointed out, and an efficient one is to be ready to realize reliable and precise detection of PPM information. The results of this study are of reference value for other modes of signal detection.
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