Balancing egoism and altruism on the single beam MIMO interference channel

Ho, Ka Ming Zuleita; Gesbert, David

This paper considers the so-called multiple-inputmultiple-

output interference channel (MIMO-IC) which has relevance

in applications such as multi-cell coordination in cellular

networks as well as spectrum sharing in cognitive radio networks

among others. We consider a beamforming design framework

based on striking a compromise between beamforming gain at

the intended receiver (Egoism) and the mitigation of interference

created towards other receivers (Altruism). Combining egoistic

and altruistic beamforming has been shown previously in several

papers to be instrumental to optimizing the rates in a multipleinput-

single-output interference channel MISO-IC (i.e. where

receivers have no interference canceling capability). Here, by

using the framework of Bayesian games, we shed more light

on these game-theoretic concepts in the more general context

of MIMO channels and more particularly when coordinating

parties only have CSI of channels that they can measure directly.

This allows us to derive distributed beamforming techniques. We

draw parallels with existing work on the MIMO-IC, including

rate-optimizing and interference-alignment precoding techniques,

showing how such techniques may be improved or re-interpreted

through a common prism based on balancing egoistic and altruistic

beamforming. Our analysis and simulations currently limited

to single stream transmission per user attest the improvements

over known interference alignment based methods in terms

of sum rate performance in the case of so-called asymmetric


Communication systems
Eurecom Ref:
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