Impact of Delayed Limited Feedback on the Sum-Rate of Intercell Interference Nulling
Users in a multicell cooperative system can feedback Channel State Information (CSI) of desired and interfering channels to the base station(s) using finite-bandwidth links to manage co-channel interference. Hence, the available feedback resources need to be partitioned efficiently between the multiple channels. In this paper, a feedback-bit allocation strategy is proposed for intercell interference nulling. The approach takes into account the received signal strengths and delays in the feedback and backhaul links. Closed-form expressions for bit partitions are derived, to allocate more bits to quantize the strong interferers with small delays and assign fewer bits to weak channels with large delays.