An Investigation into Initial Ranging Method for Mobile OFDMA Systems

This paper addresses initial ranging, which includes multiuser ranging code detection, multiuser timing offset estimation and multiuser power estimation at the base station for TDD OFDMA systems. By means of ranging signal design, our proposed ranging method overcomes the existing ranging method´s drawbacks namely high complexity, high sensitivity to channel frequency selectivity and time selectivity. Comparisons with the existing methods [1] [2] corroborate the advantages of our method in time-varying mobile environment.