PHS is the Choice for Mission-Critical Indoor Voice and Data Communications Worldwide

One of the favorite applications of PHS technology is as personal indoor cordless systems in the office, factory, hotel, hospital, hall, etc. So many systems are working in various locations worldwide. Its terminals have become smaller and lighter than ever, and enable high-speed data transmission.

Meanwhile, there have been demands from users for the expansion of indoor cordless communications service areas. To meet these demands, the additional service of inter-office PHS roaming has been adopted in many businesses. This service enables PHS users traveling from one business site to another to originate and receive calls as an extension of the PBS systems.

The features of inter-office PHS roaming service built into private networks are:

1) A PHS terminal has one number in the network and its user can originate or receive calls anywhere of the sites within the private network, as the network system automatically tracks the whereabouts of the PHS terminals;
2) The Users can introduce the service among multiple vendors’ systems and also select PHS terminals from multiple vendors as the transmission protocol between PBXs used for the service complies with the standards of the Telecommunication Technology Committee (TTC).

Figure 1 shows an example of network configuration for the service. PBXs installed in multiple sites are connected with each other via ISDN leased circuits to transmit roaming signals.
This inter-office PHS roaming service spur the introduction of PHS systems in the businesses who have the sites in various location. Besides this, another service is also available that a pre-registered public PHS terminal can automatically originate and receive calls as an extension of the PBX in the business site toward realization of seamless communication.