Power amplifier switching/selection (PAS) for energy efficient MIMO systems

We propose a power amplifier (PA) switching/selection (PAS) method to improve energy efficiency (EE) of a multiple-input multiple-output (MIMO) system. The prosposed system consists of multiple dissimilar low maximum-output (MaxOut) PAs in addition to multiple identical high-MaxOut PAs. We select the most energy efficient PAs among all PAs and the corresponding power level such that a target rate is supported. The average EE of the MIMO system is improved compared to the case of using identical PAs whether with or without power control, especially in the regime of low target rate where the low-MaxOut PAs is most energy efficient in. Numerical results verify the efficacy of the proposed PAS with respect to MIMO systems with identical PAs with the same amount of feedback for PAS.