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Public Safety Mission Critical Voice

PSCR Mission Critical Voice Research Area Logo

The MCV portfolio is focused on four areas of mission critical communications for first responders: direct mode, mission critical push to talk, LMR to LTE, and public safety user quality of experience.

Internal Research Projects

  • MCPTT Data Collection and Call Modeling
  • D2D Modeling
  • Legacy LMR to MCPTT
  • MCPTT Modeling
  • MCV KPI Development
    • Access Time Expansion
    • Access MRT
    • Volume Impact Project
  • NIST List of Certified Devices and 3GPP RAN5
  • QPP Modeling

Mission Critical Voice QoE Mouth-to-Ear Latency Measurement Methods

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 (MCV) 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 here.


Mission Critical Voice Portfolio logo in black and white

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. 

Created September 20, 2017, Updated April 28, 2020