An initial ranging scheme for IEEE 802.16 based OFDMA systems

The IEEE 802.16 family of standards for nomadic wireless metropolitan area networks adopts orthogonal frequency-division multiple-access as an air interface. In these systems, timing errors between the uplink signals and the base station time scale reference give rise to interchannel interference as well as multiple-access interference, which severely degrade the error-rate performance. In this work, we present a novel ranging scheme for initial uplink synchronization in an IEEE 802.16 based system. In contrast to existing alternative methods, our approach provides better results by properly taking into account the effects of multipath distortions on the received waveform. Numerical simulations are used to demonstrate the effectiveness of the proposed solution.