关键词: 水声通信/
循环移位扩频/
循环移位能量检测器/
时间反转镜
English Abstract
Cyclic shift keying spread spectrum underwater acoustic communication using time reversal energy detector
Du Peng-Yu,Yin Jing-Wei,
Zhou Huan-Ling,
Guo Long-Xiang
1.Acoustic Science and Technology Laboratory, Harbin Engineering University, Harbin 150001, China;
2.College of Underwater Acoustic Engineering, Harbin Engineering University, Harbin 150001, China
Fund Project:Project supported by the National Natural Science Foundation of China (Grant Nos. 51179034, 61471137) and the Ship Pre-research and Support Technology Foundation, China (Grant No. 13J3.1.5).Received Date:29 May 2015
Accepted Date:28 August 2015
Published Online:05 January 2016
Abstract:The fluctuation of sea surface and the Doppler effect cause carrier phase fluctuations of received signal, and the multipath expansion of the underwater acoustic channel makes received signal distorted, which can seriously influence the decoding performance of the cyclic shift spread spectrum system. In this paper, we propose cyclic shift energy detector (CS-ED) algorithm for cyclic shift keying spread spectrum system, which can solve the problem about the influence of carrier phase fluctuation by detecting the output energy of cyclic shift matched filter. The CS-ED combined with time reversal mirror is further proposed and analyzed in this paper by using a time-updated channel impulse-response estimate as a (match) filter to do time reversal processing to mitigate the multipath-induced interferences. Time reversal CS-ED method is simple and robust, which can make the system work in low SNR. Dalian Sea test validation and Lianhua lake test validation are carried on, showing that the low bit error rate underwater acoustic communication is achieved under the condition of multi-path extension, carrier phase fluctuation and low signal-to-noise ratio.
Keywords: underwater acoustic communication/
cyclic shift spread spectrum/
cyclic shift energy detector/
time reversal mirror
