Title :
A unified approach to time diversity combining for fast frequency hopped NCMFSK-anti-jam processing
Author :
Gulliver, T.A. ; Felstead, E.B. ; Ezers, R.E. ; Wight, J.S.
Author_Institution :
Dept. of Syst. & Comput. Eng., Carleton Univ., Ottawa, Ont., Canada
Abstract :
Frequency hopping (FH) spread spectrum is used in communications systems to provide protection against jamming. With fast FH, there are L⩾1 hops per data symbol transmitted. In the presence of severe interference, additional protection can be obtained by processing the LM values obtained from the demodulator. This processing is termed diversity combining. Many powerful and robust types of diversity combining have been developed to reduce the effects of a large jamming signal on some of the L hops. In this paper, a survey of combining methods is presented. Simulation performance results are given for severe noise and multitone jamming (SJR=0.0 dB). It is found that bit error rates as high as 0.4 can be reduced to <0.1 for L<10 using any of several diversity combining methods
Keywords :
coding errors; demodulation; demodulators; diversity reception; error statistics; frequency hop communication; frequency shift keying; interference suppression; jamming; military communication; pseudonoise codes; signal processing; spread spectrum communication; anti-jam processing; bit error rates; data symbol; demodulator; diversity combining; fast frequency hopped NCMFSK; jamming protection; military radio systems; multitone jamming; noise; simulation performance results; spread spectrum communications systems; time diversity combining; Bit error rate; Demodulation; Diversity methods; Diversity reception; Frequency diversity; Interference; Jamming; Noise robustness; Power system protection; Spread spectrum communication;
Conference_Titel :
Military Communications Conference, 1994. MILCOM '94. Conference Record, 1994 IEEE
Conference_Location :
Fort Monmouth, NJ
Print_ISBN :
0-7803-1828-5
DOI :
10.1109/MILCOM.1994.474006
