Title
Adaptive beamforming in interference networks via bi-directional training
Abstract
We study distributed algorithms for adjusting beamforming vectors and receiver filters in multiple-input multiple-output (MIMO) interference networks, with the assumption that each user uses a single beam and a linear filter at the receiver. In such a setting there have been several distributed algorithms studied for maximizing the sum-rate or sum-utility assuming perfect channel state information (CSI) at the transmitters and receivers. The focus of this paper is to study adaptive algorithms for time-varying channels, without assuming any CSI at the transmitters or receivers. Specifically, we consider an adaptive version of the recent Max-SINR algorithm for a time-division duplex system. This algorithm uses a period of bi-directional training followed by a block of data transmission. Training in the forward direction is sent using the current beam-formers and used to adapt the receive filters. Training in the reverse direction is sent using the current receive filters as beams and used to adapt the transmit beamformers. The adaptation of both receive filters and beamformers is done using a least-squares objective for the current block. In order to improve the performance when the training data is limited, we also consider using exponentially weighted data from previous blocks. Numerical results are presented that compare the performance of the algorithms in different settings.
Year
DOI
Venue
2010
10.1109/CISS.2010.5464742
Information Sciences and Systems
Keywords
DocType
Volume
channel state information,multiple-input multiple- output interference networks,max-sinr algorithm,receiver filters,least- squares objective,antenna arrays,wireless networks,multiple antennas,array signal processing,time-division duplex system,radio networks,bi-directional training,time-varying channels,least squares approximations,mimo communication,filtering theory,adaptive beamforming,transmit beamformers,transmitters,vectors,difference set,distributed algorithms,linear filtering,interference,distributed algorithm,data transmission,information theory,signal to noise ratio,least square,mimo
Conference
abs/1003.4764
ISBN
Citations 
PageRank 
978-1-4244-7417-2
10
1.05
References 
Authors
9
3
Name
Order
Citations
PageRank
Changxin Shi122712.91
Randall A. Berry2106696.64
Michael L. Honig32971411.29