Green Receivers for Massive MIMO Systems: A Joint Approach of Antenna Turn-Off and Multi-Level-Mixed-ADC Resolution Design

Abstract

In this paper, two green receivers with antenna turn-off and multi-level-mixed-ADC resolution design are proposed for massive MIMO systems, such as 5G networks and Internet of Things (IOT). For practicality, a generic power consumption model for massive MIMO receivers, including ADC resolution, symbol detection, and receiver circuits, is considered. The two proposed green receivers are formulated to minimize power consumption with respect to their individual spectral efficiency (SE) constraints, which are aimed at obtaining the optimal solution of the number of active receive antennas and corresponding multi-level-mixed-ADC resolutions. First, the proposed schemes enable the number of active receive antennas to be equal to the number of receive antennas. Second, a variant of the decremental searching and dynamic programming (DSDP) method is conducted to obtain the correspondingly optimal candidate of the multi-level-mixed-ADC resolution. Third, decrease the number of active receive antennas by 1 and then conduct the variant of DSDP again to search the correspondingly optimal resolution candidate of multi-level mixed ADCs. Fourth, repeat these mechanisms to obtain all optimal multi-level-mixed-ADC resolution candidates for different numbers of active receive antennas. Last, the number of active receive antennas and the corresponding multi-level-mixed-ADC resolution candidate, which achieve the minimum power consumption, are chosen as the optimal solution. In addition, a novel mechanism for accelerating the work of searching the number of turn-off antennas has been designed in the proposed receivers. The simulation results show that compared to DSDP, the two proposed green receivers can provide the advantage of the adjustable flexibility of power consumption with different SE requirements.