PERFORMANCE EVALUATION OF SLOW-FREQUENCY-HOPPING SPREAD-SPECTRUM TRANSMISSION IN RAYLEIGH FADING INDOOR CHANNELS

This paper examines the retransmission probability and throughput char acteristics of slow-frequency-hopping spread spectrum transmission in Rayleigh fading indoor channels of multi-cell environments. Because si gnal strength in a Rayleigh fading indoor channel changes slowly, retr ansmission probability is little influenced by the retransmission unit length and eff or correction capability when retransmission unit leng th is shorter than the fading period. With the 83.5 MHz bandwidth of t he 2.4 GHz ISM (Industrial, Scientific, and Medical) band in the USA, quaternary phase shift keying (QPSK) is expected to provide a throughp ut of nearly 1 Mbps in each cell when we assume a shadowing margin of 18.1 dB and we use 4 cells, 100 hopping frequencies, a transmission po wer of 600 mW, and a transmission distance of 20 m. And also with the 26 MHz bandwidth of the 2.4 GHz ISM band in Japan, QPSK is expected to provide a throughput of nearly 1 Mbps in each cell under similar cond itions but with 26 hopping frequencies and a transmission power of 260 mW.