2021/04/12 by I. Zakir Ahmed, Hamid Sadjadpour, Shahram Yousefi
Computer Science · Engineering · Mathematics · #cs.IT #eess.SP #math.IT
paper · pdf · doi:10.1109/tgcn.2020.3039282
published as EEE Transactions on Green Communications and Networking, vol. 5, no. 1, pp. 61-71, March 2021 · arXiv admin note: text overlap with arXiv:1902.03375
arxiv created 2021/04/12 · arxiv updated 2021/04/13
Fixed low-resolution Analog to Digital Converters (ADC) help reduce the power consumption in millimeter-wave Massive Multiple-Input Multiple-Output (Ma-MIMO) receivers operating at large bandwidths. However, they do not guarantee optimal Energy Efficiency (EE). It has been shown that adopting variable-resolution (VR) ADCs in Ma-MIMO receivers can improve performance with Mean Squared Error (MSE) and throughput while providing better EE. In this paper, we present an optimal energy-efficient bit allocation (BA) algorithm for Ma-MIMO receivers equipped with VR ADCs under a power constraint. We derive an expression for EE as a function of the Cramer-Rao Lower Bound on the MSE of the received, combined, and quantized signal. An optimal BA condition is derived by maximizing EE under a power constraint. We show that the optimal BA thus obtained is exactly the same as that obtained using the brute-force BA with a significant reduction in computational complexity. We also study the EE performance and computational complexity of a heuristic algorithm that yields a near-optimal solution.