Performance of Downlink CoMP in LTE Evolution under Practical Constraints

It has been recognized that a primary method of further enhancing the downlink spectral efficiency of LTE Release-10 is to introduce support for coordinated multi-point (CoMP) transmission. This paper investigates the performance improvements due to downlink CoMP within the framework of LTE evolution (specifically LTE Release-11). A realistic estimate of achievable CoMP throughput performance is provided with respect to variations in deployment scenario, amount of feedback information and at different traffic loads. It is observed that the performance gains due to CoMP are limited to cell edge UE (user equipment, aka mobile) throughput improvements of up to 30%. Further, we show that dynamic cell selection can realize most of the CoMP gains with less feedback than joint transmission and it is more robust under practical conditions.?