Future improvements to wideband CDMA
Sorour Falahati, Pål Frenger, Ann‐Louise Johansson, Pål Orten, Tony Ottosson Gadd, Arne Svensson · 1999
CDMA is a key technology to be used for 3rd generation personal communication systems. In this paper we first give a brief overview of the ETSI wideband CDMA (WCDMA) system. Research to improve WCDMA and similar systems is however still ongoing and we will describe some of the key aspects that we believe will be important in the near future. In a WCDMA system, the performance and the capacity are limited by interference. This may be circumvented by using more sofisticated multiuser detectors, and/or more powerful channel codes. The discussed techniques improves the capacity of WCDMA with several orders. Furthermore, we discuss coding schemes for packet data transmission, which is believed to be the main switching technique in future. Adaptive coding schemes with Viterbi decoding and tailbiting sequential decoders are presented and they both significantly improve the throughput. 1 Overview of WCDMA Here we give a short description of the Wideband CDMA (WCDMA) system as described in exi...