While P25, LMR, and LTE broadband are different technologies; you do not need to choose one or the other. P25, LMR, and Broadband are in fact "better together."

Project 25 has over 3600 LMR systems on the air today offering Public Safety Grade PTT communications to First Responders nationwide. New Public Safety Broadband LTE systems offer expanded coverage and new features requiring higher data rates. Many users question what type of Mission Critical PTT Interworking will be available between the two technologies.

First, a P25 System Administrator's expectations for LMR/LTE Interworking. Then, a newly published "Study of Interworking between P25 LMR and 3GPP (MCPTT) Mission Critical Services" report from TIA TR-8 (responsible for P25 Standards) and The Alliance for Telecommunications Industry Solutions (ATIS) will be presented. This report includes scenarios and considerations for the use of a 3GPP Interworking Function (IWF) to enable interoperability of common standard services between LMR and LTE. Multiple LMR systems are examined: P25 Trunking, Conventional, and TIA-603 analog Conventional FM. Also included are P25 features that do not have analogous 3GPP features and may not be expected to interoperate.

To conclude, concept definitions on the best use of P25 Standards based Interfaces to interoperate with the diverse set of LTE networks and products will be shared. The Interfaces include the P25 Common Air Interface (CAI), P25 Inter SubSystem Interface/Console SubSystem Interface (ISSI/CSSI), and the P25 Digital Fixed Station Interface (DFSI) The concepts show what a First Responder agency could do to extend their P25 System for LTE Interworking.

Takeaway

• What Standard Services are common between LMR and LTE?
• How can P25 Standard Interfaces best be used to create interworking with LTE Broadband Systems and devices?
• What is the future view for the evolution of interworking between LMR and LTE technologies