<title>Time code division multiple access: a multiple access technology for indoor wireless communications</title>

Abstract

Multiple access technology is important for wireless mobile radio communication systems to improve the system performance and capacity. According to the indoor radio channel characteristics we propose a multiple access scheme--the Time Code Division Multiple Access (TCDMA) for indoor wireless applications with a carrier frequency 2.4 GHz by combining advantages of both Time Division Multiple Access and Code Division Multiple Access. For implementation of a TCDMA system we use Surface Acoustic Wave devices with delays less than 5 microsecond(s) as analog Matched Filter in the receiver. The indoor multipath fading channel is modeled taking into account the measurement results for investigation of the TCDMA system capacity. Spreading codes for synchronization with maximal linear code sequences and for user data with Gold code sequences are selected according to their properties of autocorrelation and crosscorrelation. Additionally, data detection techniques are used to combat the multipath fading. Simulation results presenting bit error rate versus number of the active users are provided to prove the feasibility of TCDMA system for indoor applications.© (1995) COPYRIGHT SPIE--The International Society for Optical Engineering. Downloading of the abstract is permitted for personal use only.