Effective emergency and natural disaster management depend on the efficient mission-critical voice and data communication between first responders and victims. Land mobile radio system (LMRS) is a legacy narrowband technology used for critical voice communications with limited use for data applications. Recently, long term evolution (LTE) emerged as a broadband communication technology that has a potential to transform the capabilities of public safety technologies by providing broadband, ubiquitous, and mission-critical voice and data support. For example, in the United States, FirstNet is building a nationwide coast-to-coast public safety network based on LTE broadband technology. This paper presents a comparative survey of legacy and the LTE-based public safety networks, and discusses the LMRS-LTE convergence as well as mission-critical push-to-talk over LTE. A simulation study of LMRS and LTE band class 14 technologies is provided using the NS-3 open source tool. An experimental study of APCO-25 and LTE band class 14 is also conducted using software-defined radio to enhance the understanding of the public safety systems. Finally, emerging technologies that may have strong potential for use in public safety networks are reviewed.
We review the LTE-based FirstNet architecture in the United States, the convergence of LTE-LMR technologies, and support for mission-critical PTT over LTE, which are not addressed in earlier survey articles such as @cite_186 @cite_211 . In addition, a unified comparison between LMRS and LTE-based PSN is undertaken in and , which is not available in existing survey articles on PSC to our best knowledge. Study of LMRS and LTE band class 14 is carried out using NS-3 simulations, and software-defined radio (SDR) measurement campaigns for LMRS and LTE band class 14 technologies are reported. Different than existing literature, we also provide a comprehensive perspective on how emerging wireless technologies can shape PSN and discuss open research problems.
@cite_211 @cite_186
2066349561 2028868724
Public Safety (PS) organizations bring value to society by creating a stable and secure environment. The services they provide include protection of people, environment and assets and they address a large number of threats both natural and man-made, acts of terrorism, technological, radiological or environmental accidents. The capability to exchange information (e.g., voice and data) is essential to improve the coordination of PS officers during an emergency crisis and improve response efforts. Wireless communications are particularly important in field operations to support the mobility of first responders. Recent disasters have emphasized the need to enhance interoperability, capacity and broadband connectivity of the wireless networks used by PS organizations. This paper surveys the outstanding challenges in this area, the status of wireless communication technologies in this particular domain and the current regulatory, standardization and research activities to address the identified challenges, with a particular focus on USA and Europe. Public safety communications users in the United States are living in times of unprecedented change. From the challenges associated with the FCC's recent LMR narrowbanding mandate, which limited mobile radio channel bandwidths to 12.5 kHz, to the creation of FirstNet, the world's first, all-LTE public safety broadband network, public safety practitioners are changing the way they react and communicate during times of need. Though the network architecture for FirstNet has yet to be defined, an IMS-based VoLTE solution is the likely voice application successor to LMR push-to-talk and group calling. However, it remains to be seen whether or not VoLTE can provide the features and quality of service that public safety professionals have come to expect and rely on. And the problem is not confined to emergency responders in the United States - the worldwide community of P25 and TETRA users are evaluating the value of migrating to an LTE-based emergency communications network as well. This paper offers a high level discussion on the history of LMR, the basics of LTE and VoLTE, and implementation and testing recommendations based on possible FirstNet architectures.