Interference Avoidance In MC-DS-CDMA

Abstract

Recent trends in wireless communication have led to the shift in attention towards multicarrier modulation. In this thesis, the multicarrier communication used is hybrid MC-DS-CDMA in which the information data is spread in both time and frequency domain. These types of spreading code are termed as two dimensional orthogonal variable spreading factor (2D-OVSF) codes. This hybrid CDMA is having the advantages of both MC-CDMA and MC-DS-CDMA. In this thesis, we are going to characterize another metric-MAI Coefficient which will anticipate the effect of MAI with the time and frequency domain spreading in a particular channel. With the assistance of this MAI coefficient, a novel interference avoidance code assignment strategy is proposed. By mutually considering the acquired MAI impact and the blocking probability in the code tree structure, the proposed strategy can successfully decreasing the MAI for the multi-rate MC-DSCDMA framework, while keeping up great call blocking rate execution.