Spread spectrum S-CDMA for personal communication services

The authors examine the use of spread spectrum radios for personal communication services (PCS). Both theoretical and practical issues are presented to show the overall capacity advantage of spread spectrum CDMA (code division multiple access) over conventional narrowband FDMA (frequency division multiple access) and TDMA (time division multiple access). A PCS and wireless PBX system under development is described. The system uses synchronous-CDMA and TDD techniques to achieve full frequency reuse. A new error bound for an interference limited channel such as that encountered in the PCS network is derived. Computer simulation results indicate that a 6-10-fold increase in capacity over TDMA techniques can be achieved