Orthogonal sequency division modulation-a novel method for future broadband radio services

The third generation mobile radio systems such as the future public land mobile telecommunications system (FPLMTS) or universal mobile telecommunications system (UMTS) will supply a wide range of services and bit rates from speech transmission of a few kbit/s to video transmission of 2 Mbit/s for a user. Different techniques have been proposed to cope with the severe frequency selective fading at the high end of the data rates. Especially orthogonal frequency division multiplexing (OFDM) has received attention previously. The authors propose a novel multicarrier modulation method, orthogonal sequency division multiplexing (OSDM), which is based on orthogonal Walsh functions. This method can easily be combined with the DS/CDMA capabilities and the RAKE reception in combating multipath effects. It also makes possible coherent demodulation (even over the up-link) by efficiently inserting a pilot signal. The performance of this system is investigated for a maximal-ratio combining receiver under multipath, slowly Rayleigh fading and frequency selective channels with equal multipath intensity profiles. Both results from the analysis and the simulation suggest that this scheme is an attractive candidate for the broadband data transmission