New Research Addresses LMR to LTE Interworking
Wednesday, March 06, 2019 | Comments

Interworking between LMR and Long Term Evolution (LTE) is feasible without the Project 25 (P25) Inter RF Subsystem Interface (ISSI), according to research from Catalyst Communications Technologies following a Department of Homeland Security (DHS) grant to research interworking.

The study of LMR to LTE interworking requirements and existing standards also found interworking features vary with each radio system. The research study Catalyst began in early 2018 to analyze how a standards-based interworking solution could enable mission-critical communications between users of LMR systems and users on cellphones with push-to-talk (PTT) applications.

The research was undertaken to determine the feasibility and the architecture of a reliable, secure, and standards-based LMR/P25 to LTE mission-critical network interface service for the different LMR systems in use the current LMR systems and new LTE systems being deployed, including the First Responder Network Authority (FirstNet).

As part of the research, Catalyst determined how well public-safety requirements could be met using existing standards, including Third Generation Partnership Project (3GPP) for LTE and P25, Digital Mobile Radio (DMR) and TETRA for LMR. The company also considered the viability of interworking LTE with current analog and proprietary-based LMR systems. Catalyst concluded that existing standards did support interworking and made recommendations for ISSI extensions.

The research foundation was the National Public Safety Telecommunications Council (NPSTC) report “Public Safety Land Mobile Radio (LMR) Interoperability with LTE Mission Critical Push to Talk.” Of the 56 core requirements identified in the report and other documents, Catalyst research determined and scored a 76 percent conformance using ISSI with a Phase 2 P25 trunking system on the LMR side. Catalyst determined and scored different conformance results for other radio systems and quantified each system’s rating, primarily dependent of its interoperability interface.

The research also uncovered the need for a non–ISSI-based interworking solution for users who did not have, or could not afford, the P25 ISSI interface on their current LMR system. Catalyst conceived an “adapter” product that expands access to mission-critical PTT (MCPTT) interworking for LMR without ISSI and for LMR-to-LMR interoperability. Catalyst will develop an interface service/server, anticipated to be a software product running on a standard networked computer or computers, that will satisfy the interworking requirements defined in the NPSTC report.

Would you like to comment on this story? Find our comments system below.

Post a comment
Name: *
Email: *
Title: *
Comment: *


No Comments Submitted Yet

Be the first by using the form above to submit a comment!


November 2022

8 - 10
Communications Marketing Conference (CMC)
Albuquerque, New Mexico

March 2023

27 - 30
International Wireless Communications Expo (IWCE) 2023
Las Vegas

More Events >

Site Navigation