关键词: 多点协作, 有限反馈, 信道延迟

Abstract:

Based on clustered base station (BS) coordination and the channel delay and limited feedback in practical systems, the expressions for the data rate and rate loss upper bound per cell are derived with imperfect channel state information (CSI). Thus, given the affordable rate loss, the minimum number of feedback bits can be calculated using the upper bound. Duo to the fact that this value is derived from the upper bound, it is not very accurate. Numerical results show that the rate loss reduces when the number of feedback bits increases and the channel delay decreases. On the other hand, when the channel delay increases gradually, the rate loss can be improved little by the increase of feedback bits. Meanwhile, as SNR increases, the system performance with the imperfect CSI improves more slowly than that with the perfect CSI.

Key words: cooperative multiple points, limited feedback, channel delay