International Journal of Electrical and Computer Engineering (IJECE) Vol. 11, No. 6, December 2021, pp. 5153~5159 ISSN: 2088-8708, DOI: 10.11591/ijece.v11i6.pp5153-5159  5153 Journal homepage: http://ijece.iaescore.com Unmanned aerial vehicle-aided cooperative regenerative relaying network under various environments Thanh-Luan Nguyen 1 , Duy-Hung Ha 2 , Phu Tran Tin 3 , Hien Dinh Cong 4 1,3 Faculty of Electronics Technology, Industrial University of Ho Chi Minh City (IUH), Vietnam 2 Wireless Communications Research Group, Faculty of Electrical and Electronics Engineering, Ton Duc Thang University, Ho Chi Minh City, Vietnam 4 Goldwind International Vietnam Co. Ltd., Ho Chi Minh City, Vietnam Article Info ABSTRACT Article history: Received Dec 31, 2020 Revised May 6, 2021 Accepted May 17, 2021 This paper studies a cooperative relay network that comprises an unmanned aerial vehicle (UAV) enabling amplify-and-forward (AF) and power splitting (PS) based energy harvesting. The considered system can be constructed in various environments such as suburban, urban, dense urban, and high-rise urban where the air-to-ground channels are model by a mixture of Rayleigh and Nakagami-m fading. Then, outage probability and ergodic capacity are provided under different environment-based parameters. Optimal PS ratios are also provided under normal and high transmit power regimes. Finally, the accuracy of the analytical results is validated through Monte Carlo methods. Keywords: Air-to-ground channel Amplify-and-forward Energy harvesting Ground-to-air channel Unmanned aerial vehicle This is an open access article under the CC BY-SA license. Corresponding Author: Duy-Hung Ha Wireless Communications Research Group Faculty of Electrical and Electronics Engineering Ton Duc Thang University Ho Chi Minh City, Vietnam Email: haduyhung@tdtu.edu.vn 1. INTRODUCTION Enhancing and prolonging the lifetime of wireless networks under various environment has been a crucial mission for future green communication networks. One promising approach is to deploy unmanned aerial vehicles (UAVs) into practices to meet various exceptional requirements in different environment, e.g., disastrous land site, military in mountainous areas, and traffic control in dense urban [1]-[6]. Among these applications, ground equipments served by UAVs can either experience line-of-sight (LoS) or non-line-of- sight (nLoS) links. Therefore, UAV can play a major role in enhancing throughput as well as greatly improve reliability [7], [8]. Exploiting UAV as a relay in cooperative communication scenarios has attracted many researchers and there are still ongoing works on such topics. In fact, UAV possess flexible deployment characteristics and thus various systematic parameters such as average throughput, and spectral efficiency, can be greatly enhanced by optimizing UAV placement in 3D Euclidean space, i.e., trajectory optimization [9]-[14], deploying multiple-UAV to assist ground equipment [13], [14], power control [15], [16] and resource allocation [17]. Power splitting-based energy harvesting (PSEH) has been viewed as a future technology that can exploit a portion of radio frequency (RF) signal to recharge the battery in energy-constrained equipment [18]. Up to now, there are many works on the performance analysis of UAV-aided cooperative relay network with PSEH. However, the performance under different communication environments exploiting A2G/G2A channel characteristic is still not reported in the literature.