## 2 Selection of Communication Technology
It uses chirp spread spectrum (CSS)-derived modulation technology that uses lower power, such frequency-shift keying (FSK) modulation, for long-range communications. LoRa is a representation of low-power wide-area network (LPWAN) technology that operates in several ISM bands. Due to LoRa's low data rate, it is only suitable for applications with small payloads, such as sensors and actuators that operate in low power mode, and is unsuitable for mission-critical services [9, 12]. Another wireless communication that operates on the existing cellular networks, particularly the LTE facilities, is the narrow-band IoT (NB-IoT). The NB-IoT is capable of coexisting seamlessly with traditional GSM, general packet radio service (GPRS), and LTE technologies [9]. It offers an excellent battery life of 8 to 10 years, low channel bandwidth, a huge coverage area, is inexpensive, and possesses a good level of network security [12]. The NB-IoT can offer greater quality of service (QoS) compared with unlicensed technologies for neighbourhood area networks (NANs) and dependable services for mission-critical grid applications, such as meter reading and home automation [9]. However, NB-IoT is a latency-insensitive technology, which makes it more applicable to those delay-tolerant applications, such as AMI services. Ultra-high frequency (UHF) is one of the wireless communication technologies that can be considered for electrical distribution substation communication. UHF is well-suited for applications that require only a small amount of bandwidth, such as monitoring or automation through the IEC 60870-5-104 protocol. Applications with modest data rate requirements and widely distributed end points, such as an extensive private broadband wireless infrastructure, may have a negative benefit-cost ratio. In these cases, newly upgraded UHF radio systems are a better fit for these requirements [13]. A major advantage of these UHF systems is their ability to scale dynamically between throughput and range. They are also suitable for mission-critical applications due to the deployment of licensed spectrum and the flexibility of private network architecture [13]. The RF mesh is a standard adopted by the Wireless Smart Utility Networks Alliance (Wi-SUN Alliance). It is for building private wireless networks based on a mesh topology, with each network node acting as a repeater. As a result, each element can be accessed directly by an access point or indirectly via another network terminal element over one or more hops [14]. In order to assure compatibility across networks and devices from different manufacturers, RF Mesh aspires to be a system built on open standards. For utility applications, RF Mesh is a well-established and practical technology. From a technological and functional standpoint, RF Mesh was designed to satisfy the requirements of critical utility applications, such as smart metering and distribution automation in the case of the electric sector [14]. Satellite communication, often known as SATCOM, is a technology that has been extensively utilised for a variety of purposes, including direct-to-home (DTH), geological monitoring, and military uses. SATCOM consists of several frequency bands such as C-band, L-band, X-band, Ku-band, and Ka-band. Due to the system's location in space, natural calamities, such as floods and earthquakes, do not effect this system, making it one of the advantages [8]. SATCOM also offers a high availability range and is suitable for deployment in areas lacking terrestrial communication facilities, as the facilities are either expensive or insufficient for domain needs [15]. The disadvantage is that data transmission will be delayed due to the great distance between the earth and the satellite system, making it unsuitable for real-time monitoring and control applications [8].