| 摘要 |
A method is disclosed that assigns each sector in a cell a unique preamble spreading code (106) and a unique long-code (116) which is concatenated with a signature-associated short code (112) to spread the data in the data field (120). The period selected for the long-code (116) can be relatively long in duration (e.g., up to hours or days in length). The widths of the transmission time slots are set equal to the length of the preambles (108). Consequently, the mobile station's random access requests (20,22,24) can be timed to start at the beginning of the slots, and detected during the preamble periods by the matched filter in the base station's random access receiver. The data field (120) of the mobile station's random access request (20,22,242) is transmitted in the slots following the preamble (108) and received by the rake receiver at the base station. However, subsequent to the preamble (108) period, the matched filter is still enabled to receive the preambles (108) of other random access requests (20,22,24). Therefore, the matched filter can be utilized continuously and more efficiently, and a significantly larger number of random access requests (20,22,24) can be processed in comparison with prior random access schemes. As such, the communications throughput and efficiency of a random access system using the present method are substantially higher than the throughput and efficiency of prior random access systems. Additionally, the length of the data field (120) is not restricted. The method of concatenated spreading of the data field (120) portion of the random access packet (20,22,24) allows a user to generate a packet which is as long as desired. Moreover, there is very little danger that the resulting packet will collide with other random access request packets (20,22,24).
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