Design of 28 GHz 64-QAM Digital Receiver

This paper presents a MIMO+beamformer architecture for millimeter-wave (mmW) 5G wireless applications. A 64-QAM digital receiver operating at 28 GHz is designed for eventual applications in orthogonal frequency division multiplexing (OFDM) 5G links. The receiver design employs a 32-element linear array, with 850 MHz bandwidth sufficient to support 512-point OFDM modulation. The proposed RF chain is aimed at establishing a wireless communication link with a bit error probability better than 10
^-5
. A design procedure is adopted to provide the required signal to noise ratio (SNR) at the input of the digital demodulator. A link budget and noise analysis has been conducted using AWR Microwave Office to evaluate the system's performance under circuit non-idealities and RF impairments, such as noise, distortion, and mismatch. The 64-QAM constellation is simulated for non-ideal conditions using manufacturer test-data and circuit parameters that are embedded into the AWR Microwave Office model. This paper presents the simulation of a single receiver. Physical implementation, measurement, verification, and extension to OFDM based 32-element beamforming arrays is reserved for future work.