Chunk Based Diversity

Abstract

In this paper we explore a multicarrier system in the downlink that applies transmit antenna diversity for multiple users with a chunk based decision. Chunks are blocks of multiple subcarriers that allow the base station to allocate resources for multiple users experiencing a similar channel. The decision of similar channels is described only by the K factor which defines the ratio of the constant part versus the Rayleigh fading part. Higher K factors, like 10 and above, of the channel ask for different strategies as the performance degrades significantly in case of transmit imported frequency diversity. This allows to create diversity for users in Rayleigh fading channels and apply coherent addition of the received signals for users in Ricean fading channels.