PERFORMANCE OF DIRECT SEQUENCE SPREAD SPECTRUM FOR INDOOR WIRELESS DIGITAL COMMUNICATION.

Direct sequence, spread spectrum modulation has many attributes suitable for digital communication in indoor wireless communication. For instance, frequency reuse is possible as spread spectrum can be used as an overlay relative to existing communication services. In addition, spread spectrum provides inherent diversity against multipath fading, which is the major impairment for reliable communication in indoor local area networks. The error performance of spread spectrum is determined for various multipath fading models. When a line of sight path cannot be established, it is found that spread spectrum diversity, antenna diversity and channel coding can be combined to give acceptable performance. In many cases, in LAN applications, spread spectrum can establish a line of sight path through its time-resolution properties and in such cases diversity is not required. Direct sequence spread spectrum, coherent, binary phase shift keying modulation from a remote terminal to a central station is considered for a star network architecture. The effect on performance of other system users' signals and noise is precisely analyzed using the method of moments. Both the bit error probability and the multipath outage are used as system performance indices.