Limited channel feedback for coordinated beamforming under SINR requirements

Abstract

We consider bit allocation for channel state information (CSI) feedback in coordinated beamforming (CB) systems. The optimization problem under consideration is to minimize the total transmission power subject to the target signal to interference and noise ratio (SINR) constraints. We obtain a suboptimal solution to the problem that provides closed-form expressions for the total feedback rate and the feedback rates of each user and its channels. The advantage of the proposed scheme over the methods with equally distributed feedback rates among the users and/or channels is demonstrated by computer simulation: the CB system employing the proposed scheme causes less outage with less transmission power.

Performance analysis of adaptive limited feedback coordinated zero‐forcing multicell systems in time‐varying channels: A practical approach

“…With coding and signal processing, the MIMO multicell coordination scheme investigates the network performance with different set of channel quality information (CQI). 20 A suboptimal solution for power minimization in limited feedback coordinated beamforming approach is discussed in Seongjin et al, 21 and the comparison of adaptive ICI cancellation between single cell coordinated transmission and multicell coordinated transmission is explored in Zhang et al 22 To enhance the performance of multiantenna systems under study, consequently, the coordination between BS and mobile stations are used to mitigate both the IUI and ICI effects on the achievable throughput of the system. 17,18 By combining beamforming methodology and multicell coordination, sum rate has been characterized for TVCs.…”

“…The expected value of IUI is also calculated in the same way defined (From Equation 21 to Equation 26) for ICI. After substituting IUI and ICI in the Equation 20, the rate loss reduces to…”

Threshold Based Limited Feedback Bit Partitioning for Interference Channels in Multicell Systems

“…This time correlation helps in determining the sum-rate under various SNR regimes [12]. Minimization of transmits power with target SNR using coordinated zero-forcing was also recently proposed [13]. Suitable expressions are derived for rate loss employing coordinated beamforming in MIMO systems by considering the time varying nature of the channel (TVC) [14][15][16].…”