OFDMA: A Broadband Wireless Access Technology

In this note, we review the design philosophies for uplink and downlink of OFDMA systems and demonstrate that OFDMA is a superior access technology for broadband wireless data network compared with traditional access technologies such as TDMA and CDMA. The main advantages of OFDMA over TDMA/CDMA stem from the scalability of OFDMA, the uplink orthogonality of OFDMA and the ability of OFDMA to take advantage of the frequency selectivity of the channel. Other advantages of OFDMA include its MIMO-friendliness and ability to provide superior quality of service (QoS).