Nonlinear phenomena in beamforming
نویسندگان
چکیده
In this paper we present a summary of nonlinear system level problems in beamforming. The paper summarizes first the nonideal phenomena in power amplifiers, mixers, and oscillators. In digital predistortion inversion of the nonlinearity is needed. Not all linear and nonlinear systems are invertible or they may have only a preinverse or postinverse. Commutation is needed in indirect learning architectures for predistortion. The spatial and temporal order of compensation of different distortions is discussed. Some numerical results are also included.
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