Performance analysis of ZF and RZF in low-resolution ADC/DAC massive MIMO systems

Large number of antennas and higher bandwidth usage in massive multiple-input-multiple-output (MIMO) systems create immense burden on receiver in terms of higher power consumption. The power consumption at the receiver radio frequency (RF) circuits can be significantly reduced by the application of analog-to-digital converter (ADC) of low resolution. In this paper we investigate bandwidth efficiency (BE) of massive MIMO with perfect channel state information (CSI) by applying low resolution ADCs with Rician fadings. We start our analysis by deriving the additive quantization noise model, which helps to understand the effects of ADC resolution on BE by keeping the power constraint at the receiver in radar. We also investigate deeply the effects of using higher bit rates and the number of BS antennas on bandwidth efficiency (BE) of the system. We emphasize that good bandwidth efficiency can be achieved by even using low resolution ADC by using regularized zero-forcing (RZF) combining algorithm. We also provide a generic analysis of energy efficiency (EE) with different options of bits by calculating the energy efficiencies (EE) using the achievable rates. We emphasize that satisfactory BE can be achieved by even using low-resolution ADC/DAC in massive MIMO.