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Mission Critical Voice

PSCR Mission Critical Voice Research Area Logo

The Mission Critical Voice (MCV) portfolio concentrates on four areas of communications for first responders: direct mode, mission critical push to talk, Land Mobile Radio (LMR) to Long Term Evolution (LTE), and public safety user quality of experience (QoE).

MCV Portfolio Pecha Kucha
MCV Portfolio Pecha Kucha
Mission Critical Voice (MCV) Portfolio overview portion of the PSCR 2021 Pecha Kucha presentation.

Mission Critical Voice Portfolio Mission:

To advance the availability and performance of mission critical voice, forge partnerships to expand their sphere of research with well-qualified universities and agencies, and be influential in the standards community by participating in regular 3GPP events.

Mission Critical Voice Portfolio Vision:

PSCR, through its research and encouragement of exploration in the area of Mission Critical Voice, will be seen as a trustworthy leader by the public safety community in regards to their voice communication needs as LTE technology becomes ubiquitous for public safety use and beyond.

Featured Project


Mouth-to-Ear (M2E) latency describes the time it takes speech input in a voice communication transmit device to be output from a receiving device, and has been identified as a key component of quality of experience (QoE) in communications. NIST's PSCR division developed a method to measure and quantify the M2E latency of any communications system transmitting audio, with specific emphasis on push to talk (PTT) devices. This measurement method is the first step in establishing QoE key performance indicators (KPI) for mission critical voice and a measurement system to quantify these QoE KPIs. Additional measurement methods will be established and published in the near future. 

Download the paper and code

Internal Research

  • Mission Critical Push-to-Talk (MCPTT) Data Collection and Call Modeling
  • Device-to-Device (D2D) Modeling
  • Legacy LMR to MCPTT
  • MCPTT Modeling
  • MCV KPI Development
    • Access Time Expansion
    • Access Modified Rhyme Test (MRT)
    • Volume Impact Project
  • NIST List of Certified Devices and 3GPP RAN5
  • Quality of Service (QoS), Priority, and Pre-emption (QPP) Modeling

Extramural Research

Quick Resources

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Created September 20, 2017, Updated February 15, 2022