High-Bandwidth Spatial Equalization for mmWave Massive MU-MIMO with Processing-in-Memory
Journal article, 2020

All-digital basestation (BS) architectures enable superior spectral efficiency compared to hybrid solutions in massive multi-user MIMO systems. However, supporting large bandwidths with all-digital architectures at mmWave frequencies is challenging as traditional baseband processing would result in excessively high power consumption and large silicon area. The recently-proposed concept of finite-alphabet equalization is able to address both of these issues by using equalization matrices that contain low-resolution entries to lower the power and complexity of high-throughput matrix-vector products in hardware. In this brief, we explore two different finite-alphabet equalization hardware implementations that tightly integrate the memory and processing elements: (i) a parallel array of multiply-accumulate (MAC) units and (ii) a bit-serial processing-in-memory (PIM) architecture. Our all-digital VLSI implementation results in 28nm CMOS show that the bit-serial PIM architecture reduces the area and power consumption up to a factor of 2× and 3×, respectively, when compared to a parallel MAC array that operates at the same throughput.

digital ASIC design


processing-in-memory (PIM)

massive multi-user MIMO

Millimeter wave (mmWave)

spatial equalization


Oscar Castañeda

Cornell Tech

Sven Jacobsson

Chalmers, Electrical Engineering, Communication, Antennas and Optical Networks


Giuseppe Durisi

Chalmers, Electrical Engineering, Communication, Antennas and Optical Networks

Tom Goldstein

University of Maryland

Christoph Studer

Cornell Tech

IEEE Transactions on Circuits and Systems II: Express Briefs

1549-7747 (ISSN) 1558-3791 (eISSN)

Vol. 67 5 891-895 9050632

Massive MIMO systems with low-resolution converters

Swedish Foundation for Strategic Research (SSF) (ID14-0022), 2015-03-01 -- 2020-02-28.

Massive MIMO systems and nonlinear hardware impairments

Swedish Foundation for Strategic Research (SSF) (SM13-0028), 2014-01-01 -- 2015-12-31.

Subject Categories

Computer Engineering

Embedded Systems

Other Electrical Engineering, Electronic Engineering, Information Engineering



More information

Latest update