## 2 Literature Review
### Relation between Communications and Safety in AHS
Despite the advantages of WSNs implementation (e.g., low cost, flexible design, and real-time monitoring), they still suffer from some significant drawbacks that restrict their application to specific areas [25]. For instance, WSNs protocols rely on the 802.15.4 standards with lower energy consumption as a primary aim. Thus, the majority of these protocols are designed for low-data-rate proximity applications, which makes them ideal in smaller environments (i.e., mining environments would require a high data rate and significant proximity). Although some 802.14.5 protocols, such as WilressHART, are built to support security in the industrial environment, ensuring confidentiality might be challenging. That is, WSNs sensors consume lower energy that limits their ability to encrypt with more secure algorithms. Private LTE (pLTE) is a viable alternative solution to traditional 802.11 technology (Wi-Fi) that could provide robust communication and evade WSNs limitations [26]. In [26], the authors demonstrate how pLTE addresses performance attributes. Additionally, they highlight how the global LTE ecosystem enables private enterprises to deploy and operate LTE networks independently of licensed service providers. Furthermore, the provision of an open-access spectrum (e.g., 3.5 GHz in the United States and 5 GHz worldwide [27]) enables organizations to deploy pLTE networks. In addition, pLTE networks guarantee adequate coverage, particularly in remote areas such as mines. It also has the potential to uplink/downlink traffic capacity, especially where video streaming is used. Subsequently, organizations with private LTE have increased control over network traffic, Quality of Service (QoS), and security, and the network can be customized to optimize reliability and latency in challenging environments, such as mining. Additionally, pLTE would reduce maintenance costs since Long-Term Evolution (LTE) infrastructure does not need as many towers as traditional Wi-Fi due to its higher spectral efficiency. It also could alleviate contention issues associated with other existing networks. In terms of security, pLTE leverages well-established cellular network security infrastructure, e.g., Classic SIM-based and non-SIM options security. Due to the above, pLTE seems to be the savior solution, although it comes with a high price tag and the assumption that there is already an infrastructure ready to be deployed. Furthermore, pLTE solutions might be subject to approval and discretion by local governments, especially when it comes to the licensed spectrum. Nowadays, several ongoing advancements proceed in the field of autonomous vehicle technologies. Specified standards developed by the IEEE team (i.e., IEEE 802.11p) for vehicular networks are known as Wireless Access for Vehicular Environment (WAVE). Furthermore, Dedicated Short Range Communications (DSRC) is one among these technologies that is deployed for short- to medium-range communications, especially for vehicular networks. The DSRC/WAVE technology has been utilized for distinct vehicular applications including infotainment, resource efficiency, and safety applications [28]. Regarding mining truck autonomy, [PERSON] and [PERSON] [29] survey the performance of different routing protocols when used for cooperative collision warning in mines. This study could serve as guidance for the design of new traffic control systems that prioritize safety applications. In addition, faster data packet dissemination is emphasized for cooperative collision notification in underground mining such as deploying 5G technology. In addition, the authors in [29] address the compatibility of vehicular networks (i.e., AHS in our case) with communication standards such as IEEE 802.11x, WiMax, and DSRC/WAVE standards. Table 2 summarizes the most recent technologies, their characteristics and limitations in AHS environments.