Sum-rate analysis of downlink channels with 1-bit feedback

Document Type

Article

Publication Date

2-1-2007

Abstract

The sum-rate capacity of a single-input singleoutput (SISO) downlink with Rayleigh flat fading channels and K users, grows as log logK when optimal scheduling is employed. However, the optimal scheduling requires that the full channel state information (CSI) for all users be available to the transmitter. In this work it is shown that the same rate growth holds even if the feedback rate from the users to the transmitter is reduced to 1-bit per fading block. A simple analysis for this setup is presented, resulting in a closed form expression for the achievable ergodic sum-rate. The mechanism of setting a suboptimal threshold is elucidated by simple lower and upper bounds to the sum-rate. Among the insights afforded by the sum-rate expression and the bounds, is that application of the sub-optimal threshold demonstrates the same scaling law as the optimal full CSI scheme, asymptotically with the number of users K. © 2007 IEEE.

Identifier

33947643617 (Scopus)

Publication Title

IEEE Communications Letters

External Full Text Location

https://doi.org/10.1109/LCOMM.2007.061464

ISSN

10897798

First Page

137

Last Page

139

Issue

2

Volume

11

Grant

ANI-0338788

Fund Ref

National Science Foundation

This document is currently not available here.

Share

COinS