摘要
A novel downlink channel state information(CSI)feedback scheme is proposed for the closed-loopbeamforming system.In the proposed scheme,mobile terminal(MT)superposes the uplink pilot on thereceived downlink pilot,forms the hybrid pilot(HP),and then transmits the HP to base station(BS)viathe uplink pilot channel.Because downlink CSI can be recovered from HP at BS side without consumingextra uplink bandwidth,the proposed scheme can achieve zero-payload CSI feedback,effectively solvingthe traditional bottleneck problems,i.e.,the heavy burden for transmitting CSI.Moreover,both MT'scomplexity and feedback delays can be reduced since the downlink channel needs not to be estimated atMT any more.Simulations verify that the proposed scheme can achieve the better MSE performance forthe uplink channel estimation than the traditional scheme,and the cost for the zero-payload CSI feedbackis some acceptable loss of feedback precision.
A novel downlink channel state information （CSI） feedback scheme is proposed for the closed-loop beamforming system. In the proposed scheme, mobile terminal （MT） superposes the uplink pilot on the received downlink pilot, forms the hybrid pilot （HP）, and then transmits the HP to base station （BS） via the uplink pilot channel. Because downlink CSI can be recovered from HP at BS side without consuming extra uplink bandwidth, the proposed scheme can achieve zero-payload CSI feedback, effectively solving the traditional bottleneck problems, i.e., the heavy burden for transmitting CSI. Moreover, both MT＇s complexity and feedback delays can be reduced since the downlink channel needs not to be estimated at MT any more. Simulations verify that the proposed scheme can achieve the better MSE performance for the uplink channel estimation than the traditional scheme, and the cost for the zero-payload CSI feedback is some acceptable loss of feedback precision.
基金
Supported by the National Natural Science Foundation of China ( No. 60872048)
the National Major Program of Science and Technology ( No.2008ZX03003-004
2009ZX03003-009)
