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Christopher J. Walton, Chic J. O'Dell


This presentation explores a low-cost method to bridge analog public safety Land mobile radio (LMR) systems into a standards based Long Term Evolution (LTE) Mission Critical Push to Talk (MCPTT) system. Design goals include robustness, cost, and the creation of a system that closely conforms to released and future standards. A proof of concept prototype that successfully bridges an analog LMR system with a standards-compliant LTE based MCPTT system was developed and tested. The results and design details are covered in this presentation.
Conference Dates
July 28-September 30, 2020
Conference Location
Boulder, CO
Conference Title
PSCR Stakeholder Meeting 2020: The Digital Experience


Digital Fixed Station Interface (DFSI), InterWorking Function (IWF), Inter-RF Subsystem Interface (ISSI), Land mobile radio (LMR), Long Term Evolution (LTE), Mission Critical Push to Talk (MCPTT), Over the Air (OTA), Push-to-talk (PTT), Radio over IP (RoIP), Software Defined Radio (SDR), Subscriber Unit (SU), User Equipment (UE)


Walton, C. and O'Dell, C. (2020), PSCR 2020_Non-ISSI LMR to LTE MCPTT, PSCR Stakeholder Meeting 2020: The Digital Experience, Boulder, CO, [online], (Accessed July 18, 2024)


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Created October 28, 2020, Updated October 29, 2020