Conference Paper

New Optimized Solution Method for Beamforming in Cognitive Multicast Transmission

Sch. of Electr. Eng. & Telecommun., Univ. of New South Wales, Sydney, NSW, Australia
DOI: 10.1109/VETECF.2010.5594325 Conference: Vehicular Technology Conference Fall (VTC 2010-Fall), 2010 IEEE 72nd
Source: IEEE Xplore

ABSTRACT The optimal beamforming for cognitive multicast transmission is nonconvex rank-one constrained optimization problem. For a solution, a popular method is the combination of relaxed convex semi-definite programming, where the rank-one constraint is dropped, and randomization. We show that in many cases, this method cannot give satisfactory solutions. As an initial step, we develop a simple alternative method, which gives much better solutions. Our simulation confirms this fact.

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