A Massive MIMO Signal Processing Architecture for GHz to THz Frequencies

Abstract

State-of-the-art wireless technology is reaching its technical limits and future technologies such as millimeter wave (mmWave), massive MIMO and full duplex transmission included in upcoming 5G standards will be key in fulfilling demands for higher data rate and spectrum efficiency. Massive MIMO systems operating in the mmWave spectrum have many advantages in terms of e.g. beamforming and channel capacity, not only for communication systems but also for radar systems. Therefore, an experimental real time massive MIMO testbed utilizing sub-6GHz and the mmWave spectrum is to be constructed at Institute of Digital Signal Processing (DSV), University of Duisburg-Essen, Germany to investigate this technology in a practical manner for indoor radar system applications. The proposed testbed will initially be implemented for sub-6GHz frequencies with more than hundred antennas and later extended to the mmWave region. Obviously, the testbed design is very complex and a detailed design study is required before implementation. This paper summarizes findings of the design study. Firstly, a theoretical model of a signal processing architecture for a massive MIMO testbed is presented. This is followed by requirements and comparison of parameters processing power, bandwidth, data throughput etc. for sub-6GHz and mmWave spectrum. Also, mapping of algorithms on heterogeneous computational resources, such as FPGA, GPU and CPU is discussed. Based on the study, parameters for the proposed testbed are selected.