OFDM/CDMA technologies for future broadband mobile communication systems
OFDM (Orthogonal Frequency Division Multiplexing) and CDMA (Code Division Multiple Access) are being used to enable broadband mobile wireless access under severe multipath fading in IMT-2000 and 5 GHz band WLAN (Wireless Local Area Networks), respectively. Both of them are expected to play important roles in future broadband mobile communication systems such as fourth generation cellular and next generation broadband WLAN. This paper overviews the features of OFDM and CDMA technologies and discusses their roles in future broadband mobile communication systems. It suggests an OFDM/CDMA approach combined with link adaptation and SDM (Space Division Multiplexing) over MIMO (Multiple Input Multiple Output) channel to achieve high transmission rate and to improve frequency utilization efficiency for high system capacity.
ofdm cdma link adaptation sdm mimo