Massive MIMO with hundreds of antennas at base station (BS), is a key technology for wireless communication in 5G standard. Using low-resolution analog to digital converters (ADCs) is an ongoing research in respond to the challenge of high power consumption of such huge number of antennas at the BS. In this paper, we analyze energy efficiency (EE) and spectral efficiency (SE) of uplink massive MIMO employing low resolution quantizers and zero-forcing (ZF) detection at the BS. Considering circuit power consumption, we propose approximate expressions for the uplink sum rate and energy efficiency of a single cell system, in which K single antenna users communicate with a base station having M antennas. These expressions are validated by performing Monte-Carlo simulation. Then, using the proposed expressions, we evaluate the effects of different parameters such as M , K, average transmit power, and number of quantization bits on the SE and EE performance of the system. Indeed, we show that there is a special M in order to maximize energy efficiency with respect to the effective system parameters.
