Transceiver Design for GFDM with Hexagonal Time–Frequency Allocation Using the Polyphase Decomposition

Mohammad Derawi,Arild Moldsvor,Evren Catak

doi:10.3390/electronics9111862

Abstract

Generalized frequency division multiplexing (GFDM) is a waveform for the next-generation communication systems to succeed in the drawbacks of orthogonal frequency division multiplexing (OFDM). The symbols of users are transmitted with the time- and frequency-shifted versions of a prototype filter. According to filtering operation, the computational complexity and processing load are high for the devices that suffer from energy consumption. The communication systems are required to support the new generation devices that need low energy consumption and low latency issues. Motivated by such demands of the next-generation communication system, we propose a novel GFDM waveform that we call hexagonal GFDM. The contributions of the hexagonal GFDM are that it: (i) supports short transmission time based on its hexagonal time–frequency allocations; and (ii) provides low latency communication with low computational complexity manner. Furthermore, we design a transmitter and receiver structure in a less complicated way with mathematical derivation by using polyphase decomposition and Fourier transform (FT) transformation. The proposed systems are realized analytically and investigated over Rayleigh fading channel model through computer simulations.

Highlights

The next-generation wireless communication system’s key features include spectral efficiency, high data rate and power consumption with the simple transceiver structure [1,2]
The time-frequency allocations of the generalized frequency division multiplexing (GFDM) allow for decreasing out-of-band (OOB) emission and peak average power ratio (PAPR) that are the main shortcomings of orthogonal frequency division multiplexing (OFDM)
The hexagonal time-frequency allocation advantages are adopted to the GFDM scheme using polyphase decomposition

Summary

Introduction

The next-generation wireless communication system’s key features include spectral efficiency, high data rate and power consumption with the simple transceiver structure [1,2]. Any time and frequency variations on the users’ transmission channel and synchronization problems cause the interference between subcarriers and symbols. The new waveforms such as filter bank-based multicarrier (FBMC), generalized frequency division multiplexing (GFDM), universal filtered multicarrier (UFMC). The time-frequency allocations of the GFDM allow for decreasing out-of-band (OOB) emission and peak average power ratio (PAPR) that are the main shortcomings of OFDM. Using time slots on GFDM allows using the hexagonal time-frequency allocation for the shorter symbol duration Based on these problems, we adopt GFDM with hexagonal time-frequency allocation for shorter symbols duration and merely the filtering processing by using polyphase decomposition for low computational complexity. In the traditional GFDM, the users’ symbols are transmitted among the time- and frequency-shifted of a prototype filter. Based on the traditional GFDM structure, we derivate the hexagonal GFDM by using polyphase decomposition

Contributions

Organization

Preliminaries

Polyphase Decomposition

System Model

Performance Evaluation

Complexity Analysis

Transmission Time Analysis

BER Performances of the Proposed Hexagonal GFDM

Conclusions