The Impact of Feedback Strategy on Multiple-Input Multiple-Output Broadcast Channels
Date Issued
2007
Date
2007
Author(s)
Chang, Jun-Han
DOI
zh-TW
Abstract
Multiple transmit antennas in a downlink channel can provide the sum rate advantage (multiplexing gain). The perfect channel information is often required at the
transmitter, however it is impractical. We consider a system in which each receiver knows the perfect channel information and transmitter only has a partial channel
information conveyed by the receivers. Two feedback algorithms are proposed to track the channel information efficiently under limited feedback. The one is tracking
channel by codebook and the other is tracking channel by sign algorithm with variable step sizes. The sum-rate of zero-forcing channel inversion on a MIMO broadcast channels is considered. Under the same feedback rate, the two proposed tracking algorithm exploiting the channel correlation in time are superior. Especially, the feedback by sign algorithm with variable step size is faster and more stable. The simulation results are compared with other algorithms.
Subjects
多輸入多輸出
廣播
回饋
MIMO
Broadcast
Feedback
Type
thesis