# Gyre Precoding and T-Transformation-Based GFDM System for UAV-Aided mMTC Network
## 1 Introduction
The authors of [12] provided an extensive review study on the evolution of non-terrestrial networks (NTNs) and highlighted partially and fully integrated ground-air-space (GAS) networks from 5G to 6G by discussing the techniques ranging from new services (e.g., Internet of things (IoT) and multi-access edge computing (MEC)), to new spectrum bands (e.g., mmWave and THz), and to new approaches (e.g., machine learning (ML)). In [13], a global energy-efficient ant colony optimization (ACO) routing algorithm for UAV-aided mMTC networks is proposed to minimize the energy consumption and extend the lifetime of the networks. Furthermore, a practical algorithm is proposed to reduce  
Figure 1: A cooperative UAV-enabled relay network. the complexity. In [14], a orthogonal frequency division multiplexing (OFDM) combined index modulation signaling scheme is incorporated with UAV communication systems and results in higher spectral efficiency, higher energy efficiency, and lower BER. Generally, the OFDM system is associated with drawbacks related to issues such as high peak-to-average power ratios (PAPR), bandwidth loss associated with the cyclic prefix (CP), and high out-of-band (OOB) emissions. To meet the challenges of fifth generation (5G) and B5G wireless communication networks to handle peak data rates of at least 1 Tb/s, over-the-air latency of 10-100 \(\upmu\)s, and user-experienced data rates of 1 Gb/s, generalized frequency division multiplexing (GFDM), non-orthogonal multicarrier modulation (MCM) scheme may be preferred in lieu of OFDM. The future generation wireless networks should target ensuring low power consumption for machine-to-machine communication and low latency for tactile internet and internet-of-things (IoT) [15]. By reducing inter-carrier interference (ICI) and inter-symbol interference (ISI) through a properly designed better than raised cosine (BTRC) pulse shaping filter, improved sinc power (ISP), parametric linear pulse (PLP), and parametric exponential (PEXP), bit error rate (BER) performance is improved in the GFDM system [16]. In [17], a complementary GFDM repeated transmission scheme is proposed to enhance BER performance for mMTC and IoT. A system model is presented by the authors of [18] to develop an Einstein product of a tensor-based precoding scheme suitable for MIMO GFDM systems. In [19], a joint data symbol detection and phase noise compensation algorithm is proposed to reduce the effects of phase noise in GFDM systems. In this present study, a cooperative UAV-aided millimeter wave (mmWave) CP-free GFDM system is proposed considering data transmission for ground mMTC. In broadband wireless communication systems, one of the most popular modulation schemes, CP-OFDM, utilizes the CP to make the frequency-selective multipath fading channel appear as flat-fading [20]. 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 [PERSON]'s hyperchaos mapping system addressed in [10]. This paper mainly deals with a multi-antenna-configured UAV-aided cooperative CP-less GFDM system for secured B5G wireless networks. The physical size of each antenna of the multi-antenna-mounted UAV is very small since mmWave transmission frequency (28 GHz) is considered for this scheme. Generally, MIMO antenna-configured systems are preferably used to enhance the diversity gain and data rate of the system concerned. As the total transmission power of the UAV is limited, a single power-amplifying section for each transmitting layer is utilized here instead of using large RF chains, and thus, any negative effect on operational life cycle of the UAV is being minimized. NOMA, GFDM, universal filtered multicarrier (UFMC), and filter bank multicarrier (FBMC) has always been regarded as an excellent contender waveform for 5G networks.