Narrow band digital land mobile telecommunications system for public utilities

摘要

As a solution to the problem of shortage of radio frequency resources in multimedia telecommunications and disaster communications, the digital signal processing technology that enables transition from analog to digital modulation modes had been developed for narrow-band land mobile telecommunications systems. The standards RCR STD-39 for the TDMA system and ARIB STD-T61 for the FDMA system had been established. In March 1999, the revised radio regulations necessary for introduction of the new narrow-band land mobile telecommunications system in the market were established. JRC has marked a high supply record of analog-type mobile radio communication systems in overseas countries as well as in Japan. Based on its much experience and expertise, JRC has developed prototypes of the base station, mobile station and base station controller for the new narrow-band land mobile telecommunications system.