Frequency Spreading Equalization in Multicarrier Massive MIMO

TL;DR

This paper introduces frequency spreading equalization (FSE) for filter bank multicarrier (FBMC) in massive MIMO systems, enhancing equalization accuracy and enabling wider subcarriers for improved bandwidth efficiency and reduced complexity.

Contribution

It develops the mathematical formulation of MMSE FSE for massive MIMO, demonstrating its advantages and guiding subcarrier selection for practical channels.

Findings

Higher bandwidth efficiency achieved

Lower complexity and sensitivity to CFO

Reduced PAPR and latency

Abstract

Application of filter bank multicarrier (FBMC) as an effective method for signaling over massive MIMO channels has been recently proposed. This paper further expands the application of FBMC to massive MIMO by applying frequency spreading equalization (FSE) to these channels. FSE allows us to achieve a more accurate equalization. Hence, higher number of bits per symbol can be transmitted and the bandwidth of each subcarrier can be widened. Widening the bandwidth of each subcarrier leads to (i) higher bandwidth efficiency; (ii) lower complexity; (iii) lower sensitivity to carrier frequency offset (CFO); (iv) reduced peak-to-average power ratio (PAPR); and (iv) reduced latency. All these appealing advantages have a direct impact on the digital as well as analog circuitry that is needed for the system implementation. In this paper, we develop the mathematical formulation of the minimum mean square error (MMSE) FSE for massive MIMO systems. This analysis guides us to decide on the number of subcarriers that will be sufficient for practical channel models.