Slotted idle signal multiple access with collision detection for two-way centralized wireless communication networks

A centralized wireless communication network in which upstream and downstream traffic is transmitted over separate channels is studied. A random multiple access scheme, slotted idle signal multiple access with collision detection (S-ISMA/CD), is proposed, together with a modification of the scheme used in advanced mobile phone service systems by applying collision detection to it. The S-G (throughput versus offered load) performance of both schemes is evaluated. The dynamic characteristics of the system with finite population on the upward channel are studied using EPA (equilibrium point analysis). It is shown that both schemes have high channel efficiency and that S-ISMA/CD has a little better performance on the downward channel