Abstract—A random beamforming (RBF) technique is proposed toachieve omnidirectional coverage for broadcast channels in multiple-antenna systems. In the proposed scheme, the time and frequency re-sources for communication are divided into many time–frequency blocks(TFBs). A random pattern is employed on each TFB, with the averagepower in all directions over many TFBs being equal. The design criteriaand detailed design of the random pattern sequence are given. We proposea basic RBF scheme and an Alamouti-enhanced scheme, as well as the cor-responding structures of the transmitter and the receiver. Simulations arecarried out for an eight-element unitary linear array with half-waveformseparation in a fast-fading channel, showing that the proposed schemegreatly outperforms the cyclic delay diversity scheme and is robust tocalibration errors and failures of radio-frequency chains.
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发表于 2013-3-19 21:00:02
