system and receiver for use in demodulating a plurality of random access request messages, process for processing random access request messages in a mobile random access system, and process for establishing communication between a mobile random access system and at least one mobile station.

摘要

A mobile communications system is provided for significantly reducing the time required to process a random access mobile-originated call. During call setup, a mobile station transmits a random access packet that includes a preamble and a plurality of fields. The information provided in these fields is used by the base station to facilitate a more efficient call setup and more quickly allocate channel resources. A system is also provided for detecting, identifying and receiving multiple random access requests. Each mobile station transmits one of a plurality of different preamble symbol patterns in a random access request packet. The base station receiver includes a plurality of accumulators, each of which is tuned to a different preamble symbol pattern. Consequently, the base station receiver can distinguish between simultaneous random access requests. This preamble symbol arrangement can also be used in conjunction with power-ramping processes, such as those used in IS-95 and CODIT systems, to provide individual power control for mobile stations making multiple random access attempts.