DocumentCode :
913112
Title :
Switched-diversity FSK in frequency-selective Rayleigh fading
Author :
Arnold, Hamilton W. ; Bodtmann, William F.
Author_Institution :
Bell Communications Research, Incorporated, Holmdel, NJ
Volume :
33
Issue :
3
fYear :
1984
Firstpage :
156
Lastpage :
163
Abstract :
This paper presents the measured performance of a 64 kbit/s switched-diversity FSK receiver subjected to simulated frequency-selective Rayleigh fading. The single receiver input is switched between two, three, or four uncorrelated Rayleigh-fading signals whenever the instantaneous receiver output falls below a threshold. The optimum level of this threshold relative to the mean signal level is relatively insensitive to frequency selectivity and vehicle speed. A nearly optimum threshold may be determined using an AGC amplifier and fixed comparator. Switched diversity is a powerful tool for combating frequency selectivity and Rayleigh fading. Two-branch switched diversity can achieve 10-2BER, with 6 dB lower SNR than that needed without diversity. In the absence of frequency selectivity, two-branch switched diversity can perform within 3 dB SNR of maximal-ratio diversity and within 1 dB of selection diversity. Switched diversity can achieve BER´s lower than the irreducible single-channel BER produced by frequency selectivity. Four-branch switched diversity typically requires 4 dB lower SNR to achieve a given BER than does two-branch switched diversity.
Keywords :
Bandwidth; Bit error rate; Delay; Diversity reception; Error analysis; Frequency diversity; Frequency modulation; Frequency shift keying; Radio frequency; Rayleigh channels;
fLanguage :
English
Journal_Title :
Vehicular Technology, IEEE Transactions on
Publisher :
ieee
ISSN :
0018-9545
Type :
jour
DOI :
10.1109/T-VT.1984.24002
Filename :
1623201
Link To Document :
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