Power allocation for multicell mixed-ADC massive MIMO systems in Rician fading channels

Abstract

This paper investigates the achievable uplink spectral efficiency (SE)of a massive multi-input multi-output (MIMO) systems with a mixed analog-to-digital converter (ADC) receiver architecture, in which some antennas are equipped with costly full-resolution ADCs while others are equipped with cheap low-resolution ADCs. We derive the theoretical results and corresponding approximate expressions of the achievable SE in single cell systems and multicell systems. Based on approximated results, analysis demonstrates that the achievable SE is decided by the transmit power, the number of antennas, the proportion of full-resolution ADCs and quantization precision of the low-resolution ADCs. Especially, we propose the power allocation algorithms based on the lower bound and upper bound of approximate achievable SE for multicell systems with Riean fading channel and MRC detector. Simulation results show that the total achievable SE improves by increasing the number of BS antennas, the signal-to-noise ratio (SNR), and the quantization precision. Moreover, by comparing the total achievable SE for the proposed power allocation algorithms and the equal power allocation algorithm, results showcase that proposed power allocation algorithms remarkably improve the total achievable SE, which verifies the effectiveness of our proposed schemes.