sartphones and computers to create a seamless and interconnected ecosystem for a wide variety of devices, ranging from IoT sensors and smart appliances to industrial machinery and urban infrastructure. The emerging 5G-enabled features that are positioned to transform our lives are presented in Figure 1.  
Table 1 provides a concise list of abbreviations and acronyms with their corresponding definitions used in this review paper. In 2015, the European Commission launched the 5G Public Private Partnership (5G PPP) initiative [1], which brought together industry and academic partners to develop \begin{table}
\begin{tabular}{c c} \hline \hline
**Abbreviation** & **Definition** \\ \hline \(\theta\) & Angle of elevation \\
3 GPP & 3 rd Generation Partnership Project \\
5G & 5 th Generation \\ ABG & Alpha–Beta–Gamma \\ CI & Close-In reference \\ \(d_{2D}\) & 2D distance between Tx and Rx \\ \(d_{3D}\) & 3D distance between Tx and Rx \\ \(d_{o}\) & Reference distance \\ dB & Decibel \\ \(f_{c}\) & Central frequency \\ FI & Float intercept \\ FSPL & Free space path loss \\ GHz & Gigahertz \\ \(h_{BS}\) & Antenna height for the base station \\ \(h_{UT}\) & Antenna height for the user terminal \\ IMT & International mobile telecommunication \\ ITU & International Telecommunication Union \\ LOS & Line-of-sight \\ MHz & Megahertz \\ mm-Wave & Millimeter wave \\ MIMO & Multiple-input multiple-output \\ NLOS & Non-line-of-sight \\ PL & Path loss \\ \(PL_{UMA-LOS}\) & Path loss for urban macro and line-of-sight scenario \\ \(PL_{UMA-NLOS}\) & Path loss for urban macro and non-line-of-sight scenario \\ RX & Receiver \\ T-R & Transmitter to receiver \\ Tx & Transmitter \\ \(UT\) & User terminal \\ WRC & World Radio Communication Conference \\ \hline \hline \end{tabular}
\end{table} 
Table 1: List of abbreviations and acronyms used in the paper. Figure 1: Transformative 5G-enabled features shaping our future. and test 5G technologies. The same year, the United States Federal Communications Commission (FCC) opened high-frequency spectrum bands for 5G networks. In 2016, the first 5G standard was released by the International Telecommunication Union (ITU) [2], followed by the 3 rd Generation Partnership Project (3 GPP) releasing the first 5G New Radio (NR) specifications in 2017. These standards and specifications defined the technical requirements and capabilities of 5G networks, including the use of higher-frequency spectrum, massive multiple-input multiple-output (MIMO) technology, and network slicing [2]. In 2018, the first 5G networks were launched in South Korea, with other countries following suit in the launching of 5G networks for a range of applications, including enhanced mobile broadband, smart cities, connected vehicles, and industrial automation. Trial and commercial system deployments are happening right now in various regions of the world, especially at frequencies below 6 GHz [3]. Delegates from the World Radio Communication Conference (WRC-19), held in Egypt, identified additional radio-frequency bands for deploying 5G mobile networks. According to the WRC-19 resolutions, larger continuous blocks of the spectrum will be needed for International Mobile Telecommunication (IMT-2020) than are currently available in the frequency bands that have already been selected for usage by administrations looking to implement 5G and other wireless communication technologies [4]. Additionally, they emphasized the necessity of uniform international bands for IMT to ease global roaming and the advantages of scale [5]. The spectrum used for 5G is divided into three (3) categories: low-band (<1 GHz), mid-band (1-6 GHz), and high band (>6 GHz); each has merits and demerits. But the mid-band is the most essential (called the priority band), as most deployments are in this band. WRC-23 is considering extending this band due to its importance--its strategic position in achieving both coverage and speed, etc.