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

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 match¬ing de¬creases 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 com¬pared with the rate matching scheme.