InterWorking Function for Mission Critical Push to Talk Services

Abstract

AbstractDue to the continuous development of mobile communication technologies, commercialized mobile communication systems have been globally deployed. Among them, LTE-A (Long-Term Evolution-Advanced) has been adopted by several countries for the next generation PSNs (Public Safety Networks). To this end, 3GPP has also standardized Mission Critical Push To Talk (MCPTT) services in Release 13. Since the LMR (Land Mobile Radio) system has been widely adopted as the primary technology of the PSNs for a long time, it will take several years for LTE-A to replace it completely. Consequently, issues related to the interconnection of the LTE-A and LMR systems have received attention. In view of this, the interconnection of LTE-A and LMR systems has been standardized in 3GPP Release 15. A new function named IWF (InterWorking Function) was introduced to enable communications between LTE-A and LMR systems. Based on the considered system architecture, this paper first presents the implementation of IWF. Then, MCPTT group call for members between LTE-A and LMR systems is used to verify the feasibility and functionality of the implemented IWF.KeywordsLTE-AMCPTTIWFLMR