Title :
Joint hop-timing estimation for FH signals using a coarsely channelized receiver
Author :
Aydm, L. ; Polydoros, A.
Author_Institution :
Commun. Sci. Inst., Univ. of Southern California, Los Angeles, CA, USA
Abstract :
This paper addresses the joint hop-timing (epoch) estimation problem for a desired frequency-hopping (FH) signal plus an interfering FH signal using a coarsely channelized pre-processor which suppresses the frequency and phase dependence of the signals. The signals are modeled with the same hop rate and candidate hop frequencies, but with distinct power and timing epochs. Coarse channelization implies a bank of filters, much smaller in number than the size of the candidate hop frequency set, which covers the total shared bandwidth. It is shown that the Viterbi algorithm can be used to efficiently implement the maximization over the frequency sequences. Performance evaluation is presented via extensive computer simulations, showing that the estimates are unbiased and consistent whenever the signal powers are distinct. When the co-channel signal-to-interference ratio increases towards one this estimator deteriorates in performance
Keywords :
band-pass filters; cochannel interference; filtering theory; frequency hop communication; maximum likelihood estimation; radio receivers; sequences; spread spectrum communication; timing; FH signals; Viterbi algorithm; candidate hop frequencies; coarsely channelized preprocessor; coarsely channelized receiver; cochannel signal to interference ratio; computer simulations; epoch estimation; filter banks; frequency dependence suppression; frequency sequences; frequency-hopping signal; hop rate; interfering FH signal; joint hop-timing estimation; performance evaluation; phase dependence suppression; power epoch; shared bandwidth; signal power; spread spectrum communication; timing epoch; Bandwidth; Filter bank; Frequency estimation; Frequency synchronization; Interference; Military communication; Phase estimation; Power system modeling; Radio transmitters; Timing;
Conference_Titel :
Military Communications Conference, 1995. MILCOM '95, Conference Record, IEEE
Conference_Location :
San Diego, CA
Print_ISBN :
0-7803-2489-7
DOI :
10.1109/MILCOM.1995.483631