I. Introduction
Modern wireless communication technologies are rapidly evolving to meet the future sixth generation (6G) requirements and to enable enhanced ubiquitous connectivity to end users with high data rates, improved reliability/versatility, and low latency. Recent reports on the advancements of fifth generation (5G) deployment show that more than 160 network operators have enabled 5G services to 290 million subscribers and projected to reach 580 million by the end of 2021 and 3.5 billion by 2026 [1]. Furthermore, 6G network deployments are anticipated to start by year 2030 [2].