Frequency-Domain Decoupling for MIMO-GFDM Spatial Multiplexing

TL;DR

This paper introduces a class of GFDM filters that eliminate inter-subcarrier interference, enabling efficient MIMO-GFDM detection through frequency-domain decoupling and sphere decoding, significantly reducing computational complexity.

Contribution

It proposes a new class of GFDM prototype filters that enable interference-free operation and simplifies MIMO-GFDM detection using sphere decoding.

Findings

Significant complexity reduction in detection for large numbers of subcarriers.

Effective frequency-domain decoupling achieved with the proposed filter class.

Validation through numerical results demonstrating improved efficiency.

Abstract

Generalized frequency division multiplexing (GFDM) is considered a non-orthogonal waveform and known to encounter difficulties when using in the spatial multiplexing mode of multiple-input-multiple-output (MIMO) scenario. In this paper, a class of GFDM prototype filters, under which the GFDM system is free from inter-subcarrier interference, is investigated, enabling frequency-domain decoupling in the processing at the GFDM receiver. An efficient MIMO-GFDM detection method based on depth-first sphere decoding is then proposed with such class of filters. Numerical results confirm a significant reduction in complexity, especially when the number of subcarriers is large, compared with existing methods presented in recent years.