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Coverage, Capacity, and Resilience Enhancement in Limited PSN

George Washington University


The next few years form a critical stage in the evolution of broadband Public Safety Networks (PSNs); we anticipate that key PSN-related issues including coverage and capacity extension methods, support for end-to-end Quality of Service Priority and Preemption (QPP), failure resilience, and multicast will be fully standardized (reach final and stable version) only after this time, given the current lack of fully-compliant chips and interoperability tests in some aspects. We have already obtained a number of important results that can inform and impact handling of Mission Critical Voice (MCV), Mission Critical Push-To-Talk (MCPTT), general QPP support, as well as general coverage enhancement, and reconfiguration methods in future PSNs. In particular, our pioneering study on the analysis of potential spectrum savings and improving first responder (FR) communications by using Multicast-broadcast single-frequency network (MBSFN) and our results on optimal selection of channel parameters for PSN applications in Long-Term Evolution (LTE) Direct are useful for MCV, MCPTT and general QPP support. Our work on FR trajectory-based mobile base station placement is important for general coverage enhancement and reconfiguration, and useful to the first responder communications and operations. Several articles are already published from the results of this research, and additional articles are expected to be submitted. - July 2019 


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Coverage, Capacity, & Resilience Enhancement in Limited Public Safety Networks
Coverage, Capacity, & Resilience Enhancement in Limited Public Safety Networks

Meet the Team

Hyeong-Ah Choi
George Washington University

Amrinder Arora
George Washington University

Yanxiang Zhao
George Washington University

Wei Cheng
Virginia Commonwealth University

Gokhan Sahin
Miami University

 


Project Overview

It is crucial to provide timely and reliable communication among the public safety (PS) team members, victims and devices involved in an emergency situation. However, such communication may be unavailable in all or parts of the incidence area for various reasons. Even in some LTE-based PS network settings, limited range (and coverage), high latency, and lack of emergency call robustness are viewed as important challenges that need to be addressed. This project considers both off-network and on-network first responder user equipment (UE). The overarching objective of this project is to extend the PSN coverage to UEs that are outside the reach of the eNB, and to provide sustained, failure-resilient coverage and capacity to both on-network and off-network UEs consistent with the dynamically changing needs, priorities, and Quality of Service (QoS) requirements of the FR in real-time.

The vision is to have a PSN that intelligently adapts and extends its coverage so as to ensure the availability of the services, bandwidth, QoS level, and reliability required by the FR wherever they go, at the right time. The overall objective of this project in this context is to support MCV communication for FRs in the broadest set of environments and situations possible.

To achieve this objective, the team’s research centers on two broad categories of enabling technologies and approaches:

  1. Prudent use of relays and mobile eNBs, including trajectory and placement optimization and real-time scheduling of relay operation (on/off) and coordination

  2. QoS, prioritization, and preemption for mission-critical communication (MCC). In conjunction with, and expanding upon these two approaches, we will also focus on addressing various PSN-specific issues and problems in network resilience and reconfiguration and LTE multicasting. This project will utilize, combine, and develop tools from algorithms, optimization, stochastic analysis, graph theory, and distributed and hybrid protocol design.

Anticipated Challenges

Prior art in LTE broadband networks has commercial focus, and is unsuitable for the dynamic, unpredictable, and hierarchical nature of PSN. Designing online and/or distributed mechanisms for dynamic FR scenarios on and off-network, on a large scale, with QPP and fault-tolerance constraints, is challenging, yet essential for PSN.

Benefits and Impacts

The next few years form a critical stage in the evolution of broadband PSNs; the team anticipates that key PSN-related issues including coverage and capacity extension methods, support for end-to-end QPP, failure resilience, and multicast will be fully standardized (reach final and stable version) only after this time, given the current lack of fully-compliant chips and interoperability tests in some aspects. Accordingly, it is important to address these issues now in order to inform and impact handling of MCV, MCPTT, general QPP support, as well as general coverage enhancement, failure resilience and reconfiguration methods in future PSN networks.

<< Back to the PSIAP 2017 - Public Safety Mission Critical Voice Page

Created September 28, 2017, Updated January 31, 2020