Broadband packet wireless access appropriate for high-speed and high-capacity throughput

This paper evaluates the optimum broadband packet wireless access scheme using a 50-100 MHz bandwidth to achieve highspeed packet transmission taking into consideration the realization of high-speed and high-capacity packet transmission, the accommodation of variable rate services with different quality requirements, and the extendibility for and commonality to the IMT-2000. In the forward link, the presented simulation results associated with the evaluation of key features show that multi-carrier CDMA (MC-CDMA) is the most promising candidate, since it achieves the highest-capacity packet transmission in a severe multipath fading channel due to a lower symbol-rate with numerous sub-carriers and a channel coding gain accompanied by the frequency diversity effect. Meanwhile, single-carrier/DS-CDMA and multi-carrier/DS-CDMA (SC/DS-CDMA and MC/DS-CDMA) are severely degraded due to significantly increasing multipath interference, and orthogonal frequency division multiplexing (OFDM) lacks efficient cell deployment due to the necessity of frequency reuse in a multi-cell environment without complicated dynamic channel assignment (DCA). Furthermore, in the reverse link, we conclude that MC(SC)/DS-CDMA is a promising candidate because it has advantages such as an effective random access method, soft handover, and an inherent property for accurate location detection.