Skip to main content
U.S. flag

An official website of the United States government

Official websites use .gov
A .gov website belongs to an official government organization in the United States.

Secure .gov websites use HTTPS
A lock ( ) or https:// means you’ve safely connected to the .gov website. Share sensitive information only on official, secure websites.

Modeling, Simulation and Performance Evaluation for Future Public Safety Networks

University of Washington

This project is exploring fundamental aspects of demand modeling for Public Safety Communications (PSC) networks, in terms of the key network Quality of Service (QoS) metrics: network capacity etc. This work hopes to shed light on key questions such as: what should be done from a network planning and resource scheduling perspective for Long Term Evolution (LTE) network to account for location and scale of various for emergency/ public safety events so as to meet capacity, coverage and QoS (latency, data rates, loss and service prioritization) requirements.

University of Washington logo

A second objective in support of performance evaluation of PSC scenarios over LTE networks is creation of a public safety simulation module within the open source ns-3 network simulator intended for the broader research community. The objective includes implementations and/or integrations of essential 3GPP features into ns-3, inclusive of

  • proximity services and mission critical push-to-talk over group communications
  • LTE Direct Mode Operation for device-to-device communications

Researchers will be able to use this tool (when tested and released formally) to conduct performance analysis studies of future public safety networks, with a high degree of modeling fidelity.

Meet the Team

Principle Investigator: Sumit Roy
University of Washington

Project Overview

This project ties together modeling using analysis and simulation along with open-source software development to deliver a demand modeling framework for emerging LTE-based public safety networks, developed in coordination with City of Seattle in the midst of a significant transition of its PSC network. The project utilizes a two-phased approach: developing first baseline stochastic approach to demand modeling, followed by validation and additional modeling that leverages the body of data provided by City of Seattle as it confronts an exponential increase in public safety wireless video traffic.

A key question the team will focus on is under what emergency scenarios can the requirements be expected to exceed the capacity of the allocated public safety spectrum in the 700 MHz band, and what should be done from a network planning and resource scheduling perspective to compensate for various scenarios so as to meet capacity, coverage and QoS (latency, data rates, loss and service prioritization) requirements. As a result, the team will work to act as neutral arbiters regarding public safety communications technology and network planning for the City of Seattle and their vendor chain.

Future public safety services over LTE networks will require progress on several key topics.  At the MAC layer within the radio access network (RAN), the team will pursue network planning and resource scheduling of the RAN for group call bearers, bearer retention schemes and emergency service flow prioritization in a public safety context, and analysis of LTE RAN scheduling options and their impact on QoS.  Further, link level analysis of LTE Direct Mode Operations (DMO) for device-to-device (D2D) communications will be conducted. Specifically, the team will explore relaying strategies while incorporating realistic D2D channel models for canonical operating scenarios via MATLAB link simulations, as inputs to subsequent network-level analysis.

In response to the call for packet-level simulation research infrastructure, the team offers an ns-3 public safety simulation module, including implementations and/or integrations of essential 3GPP features (cf. Proximity Services and MCPTT over GCSE) for public safety networks, public safety scenario support, models from the above tasks, and underlying LTE enhancements, in the packet-level open source ns-3 simulator. Outputs from the above two research thrusts will be integrated with the essential PSCR model and scenario support of this task

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

Created September 28, 2017, Updated December 30, 2022