A Novel Method to Solve CRS/PDSCH RE Collision in Joint Transmission in LTE-A

Abstract

CoMP (Coordinated multi-point) transmission and reception has been studied for deployment types such as heterogeneous networks in LTE-A Rel-11. In this paper, we focus on the CRS (cell-specific reference signal)/PDSCH (Physical Downlink Shared Channel [12]) RE (resource element) collision in downlink joint transmission where different transmission points have different CRS frequency shifts. Since CRS muting scheme with rate matching decreases PDSCH throughput, we propose to send an additional PDSCH RE over the CRS collided PDSCH REs from joint transmission points. With CRS-IC (CRS interference canceling) receiver at UE, this scheme has significant throughput gain over CRS muting in the link level simulation. In addition, this new approach doesn't have negative impact on legacy UE's interference measurements compared with the rate matching scheme.