Theoretical analyses of data communications integrated into cordless voicechannels

Dynamic integration of data into voice channels of second-generation cordle ss systems provides effective channel utilization. This paper proposes and theoretically examines an inhibit and random multiple access (IRMA) protoco l for data terminals in an integrated voice and data system by assuming tha t real-time voice traffic has priority over data. Analytical expressions ar e derived to quantify the effect of data inhibition on data performance, i. e., throughput and delay for both infinite and finite population models for data terminals. In order to find the possible data throughputs with our ch annel access scheme for data communication using voice channels while not a ffecting the voice quality, we investigate the data performance under two e xtreme situations: 1) no voice load and 2) full voice load. The numerical r esults indicate that IRMA data performance is comparable to that of slotted ALOHA (S-ALOHA) at lighter loads of less than 0.2 while efficiently sharin g the network resources between real-time voice and nonreal-time data traff ics, For the data loads above 0.2, IRMA pays a price, but an affordable one , in terms of throughput performance for its ability to accommodate data wh ile assuring quality of voice even when all channels are occupied by voice traffic. An optimum number of terminals and the range of data-transmission probabilities have been deduced as 16 and 0.05-0.15, respectively, in order to achieve maximum throughput with minimum delay while maintaining stable data transmission and voice quality in an integrated system.