Integer-Forcing MIMO Linear Receivers Based on Lattice Reduction

TL;DR

This paper introduces a novel integer-forcing linear receiver for MIMO channels using lattice reduction techniques, which improves ergodic rate bounds, achieves full diversity, and outperforms traditional linear receivers in simulations.

Contribution

It proposes a lattice reduction-based method for integer coefficients in IF receivers, connecting them with lattice reduction-aided detectors and demonstrating superior performance.

Findings

Lower bound on ergodic rate established

Achieves full receive diversity

Outperforms ZF, MMSE, and lattice reduction-aided detectors in simulations

Abstract

A new architecture called integer-forcing (IF) linear receiver has been recently proposed for multiple-input multiple-output (MIMO) fading channels, wherein an appropriate integer linear combination of the received symbols has to be computed as a part of the decoding process. In this paper, we propose a method based on Hermite-Korkine-Zolotareff (HKZ) and Minkowski lattice basis reduction algorithms to obtain the integer coefficients for the IF receiver. We show that the proposed method provides a lower bound on the ergodic rate, and achieves the full receive diversity. Suitability of complex Lenstra-Lenstra-Lovasz (LLL) lattice reduction algorithm (CLLL) to solve the problem is also investigated. Furthermore, we establish the connection between the proposed IF linear receivers and lattice reduction-aided MIMO detectors (with equivalent complexity), and point out the advantages of the former class of receivers over the latter. For the $2 \times 2$ and $4\times 4$ MIMO channels, we compare the coded-block error rate and bit error rate of the proposed approach with that of other linear receivers. Simulation results show that the proposed approach outperforms the zero-forcing (ZF) receiver, minimum mean square error (MMSE) receiver, and the lattice reduction-aided MIMO detectors.