Introduction to DMR
DMR Network Architecture
DMR Network Gateways
A network gateway is a simple device that allows a single audio channel to connect to the DMR network. It converts the AMBE voice over IP (VoIP) used by the network into analog 4-wire audio.
The network gateway allows simple interfacing of the Line Dispatch Terminal (LDT) to the DMR network. The Line Dispatch Terminal (LDT) is a PC-based dispatch console that provides a simple yet powerful interface into the DMR network. With the LDT software and associated hardware, central dispatch operations can effectively communicate with a large number of radio users. The features and functions of the LDT include:
- Simple configurable user interface
- Identify multiple simultaneous emergency and non-emergency calls from multiple users
- Displays caller/talker ID
- Display historical and missed calls
- Simple talkgroup calling
- Simple talkgroup monitor/un-monitor
- Call hold
- Call conferencing
The Network gateway provides the 4 wire audio to the LDT desktop audio interface.
Another function of a network gateway is the ability to connect an analog base station or set of analog base stations to a DMR network. The network gateway provides ENM switching to control call setup. It also provides the full wire audio link from the conventional system into the trunk system.
The network gateway can be used to control the link between a conventional set of base stations and the DMR network. They can also be used in the migration from MPT1327 analog trunked networks into a DMR trunked network solution. The gateways provide the audio and the control switching connection between the two trunked systems.