DELAY AND THROUGHPUT CHARACTERISTICS OF TH, CDMA, TDMA, AND HYBRID NETWORKS FOR MULTIPATH FADED DATA-TRANSMISSION CHANNELS

The new concepts of adaptive time hopping and variable frame Code Divi sion (CDMA) Multiple Access are introduced. By a unified analysis, the probabilities of bit and packet errors in multipath fading environmen t for five Time Division (TDMA), Code Division, and Time Hopping (TH) related multiaccess networks are obtained; namely, TDMA, CDMA, CDMA/TD MA, Adaptive CDMA/TH, and variable frame CDMA/TDMA networks. The delay and useful throughputs of the five systems are also evaluated for dat a and voice traffic. All systems compared have the same channel power and bandwidth and support the same traffic. Though implementation issu es are not covered, CDMA systems are put at a disadvantage (compared t o cellular-type FDMA networks, for example) by ignoring such inherent advantages as voice silence utilizations and automatic frequency reuse . Nontheless, two CDMA systems outperform TDMA systems at low and medi um input traffics.