Gyre Precoding and T-Transformation-Based GFDM System for UAV-Aided mMTC Network

Joarder Jafor Sadique,Shaikh Enayet Ullah,Abbas Z Kouzani,Md Rabiul Islam,Raad Raad,Md Mahbubar Rahman,M A Parvez Mahmud

doi:10.3390/electronics10232915

Abstract

In this paper, an unmanned aerial vehicle (UAV)-aided multi-antenna configured downlink mmWave cooperative generalized frequency division multiplexing (GFDM) system is proposed. To provide physical layer security (PLS), a 3D controlled Lorenz mapping system is introduced. Furthermore, the combination of T-transformation spreading codes, walsh Hadamard transform, and discrete Fourier transform (DFT) techniques are integrated with a novel linear multi-user multiple-input multiple-output (MU-MIMO) gyre precoding (GP) for multi-user interference reduction. Furthermore, concatenated channel-coding with multi-user beamforming weighting-aided maximum-likelihood and zero forcing (ZF) signal detection schemes for an improved bit error rate (BER) are also used. The system is then simulated with a single base station (BS), eight massive machine-type communications (mMTC) users, and two UAV relay stations (RSs). Numerical results reveal the robustness of the proposed system in terms of PLS and an achievable ergodic rate with signal-to-interference-plus-noise ratio (SINR) under the implementation of T-transformation scheme. By incorporating the 3D mobility model, brownian perturbations of the UAVs are also analyzed. An out-of-band (OOB) reduction of 320 dB with an improved BER of 1×10−4 in 16-QAM for a signal-to-noise ratio, Eb/N0, of 20 dB is achieved.

Highlights

An uncrewed aircraft handled by remote control or embedded computer programs is commonly known as an unmanned aerial vehicle (UAV) or drone
A UAV-aided millimeter wave (mmWave) downlink cooperative cyclic prefix (CP)-less generalized frequency division multiplexing (GFDM) system is proposed in this paper
UAVs are combined with a terrestrial cellular network, and emphasis is placed on physical layer security for massive machine-type communication users in such a network

Summary

Introduction

An uncrewed aircraft handled by remote control or embedded computer programs is commonly known as an unmanned aerial vehicle (UAV) or drone. As the CP causes overhead in the spectrum efficiency and power efficiency, the use of a CP is being avoided, and guard intervals (GIs) are being introduced between two consecutive GFDM symbols In this UAV relay-assisted terrestrial networking system, more focus is attributed to enhancing secure transmission using Lorenz’s hyperchaos mapping system addressed in [10]. GFDM is a symbol-based multicarrier multiplexing technique which keeps the signal well confined in time and frequency domains It utilizes circular filter for effective reduction in the low out-of-band (OOB) emission and ensures simultaneous transmission of multiple symbols at different time slots. By taking all these properties into account, a GFDM-aided system is presented in place of the OFDM-based signaling technique. Despreaded signals are passed through the phases of digital demodulation, channel decoding, and improved 3D controlled Lorenz mapping-based decryption to eventually recover the transmitted data

Signal Model

Ground Segment

UAV Segment

Numerical Results and Relative Discussion

Conclusions