Joint transmission using global codeword and codebook design for coordinated multipoint processing (CoMP)

In this paper we propose a joint transmission scheme for LTE-CoMP using a single codeword to transmit from multiple transmission points to a single UE. Transmission with a single codeword makes the signal better aligned with the dominant eigenmode of the channel and achieves higher capacity. A design methodology of the global codebook for joint transmission from two transmission points is developed. A codebook is created using K-mean clustering algorithm from a large number of channel samples generated through simulation. Simulation results show that this approach can outperform traditional local precoding approach where two separate codewords from the existing LTE-A MIMO codebook are used from two transmission points.