IDMA - Future of Wireless Technology

Direct-sequence code-division multiple access (DS-CDMA) has been adopted in second and third-generation cellular mobile standards. Users are separated in CDMA system by use of different signatures for ach user. In CDMA system, many users share the transmission media so that signals from different users are superimposed causing interference. This report outlines a multiple access scheme in which interleaving is the only means of user separation. It is a special form of CDMA; it inherits many advantages of CDMA such as dynamic channel sharing, mitigation of cross cell reference, asynchronous transmission, ease of cell planning and robustness against fading. Also a low cost interference cancellation technique is available for systems with large number of users in multipath channels. The normalized cost (per user) of this algorithm is independent of the number of users. Furthermore, such low complexity and high performance attributes can be maintained in a multipath environment. The detection algorithm for IDMA requires less complexity than that of CDMA. The performance is surprisingly good despite its simplicity.

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