DMR Trunk Wide Area System

DMR Trunk Wide Area System solution is offered as encrypted or non- encrypted for users;

  • Demanding use in a wide area,
  • In need of data communication and location services in addition to voice communication,
  • In need of a system management centre due to requirements such as audio / data traffic and tracking radio locations,
  • Having large number of user groups and the frequency of making calls is high,
  • It is a critical to use TDMA (Time-Division Multiple Access) because it is important to efficiently allocate the frequency in the region where the communications will be performed.
  • Generally, who are in need of communication in plain areas.

ASELSAN, DMR offers a turnkey system solution for Trunk Wide Area architecture. For this architecture, infrastructure (base stations and switching unit), end user products (both radios and applications) and integration / installation solutions are provided.

 

In TDMA technology, while a call is on the physical channel, another user may initiate a call and continue two different calls on the same physical channel while a physical channel determined in the FDMA technology (e.g., a channel with a bandwidth of 12.5 kHz) is available for only one call. When the number of time slots are increased, the number of calls that can be performed on the same physical channel increases. Since the DMR communication protocol is in the 2 time division TDMA structure, two different calls can be made on the same physical channel, thus ensuring frequency efficiency. 

In the trunk system architecture, each base station has 1 repeater radio programmed as "control channel" and repeater radios programmed as "traffic channel". All radios within the range of the base station wait on the control channel. If there is a call in any of the radio groups, all the radios in that group go from the control channel to the traffic channel assigned for that call. Other groups continue to wait on the control channel. If there are calls in the waiting radio groups, a new traffic channel is assigned for this call. The higher the number of traffic channels, the more number of groups can communicate simultaneously. When all the traffic channels in the base station are occupied, a new call is queued. It is directed, when a traffic channel is eligible.

In the conventional system architecture, one repeater radio is assigned for each channel. If this channel is occupied by any group, but one of the other groups wants to initiate a call, a warning is given that the channel is busy. The call is not queued. Trunk system architecture, a more sophisticated architecture as it can be understood from here, is a more suitable solution for users with a large number of user groups. Organizations with fewer users and fewer uses of the system may prefer to use conventional system architecture.

The following applications are supported in the DMR Trunk Wide Area System solution:

  • Vehicle and Personnel Follow-up Application,
  • Database Query Application,
  • Operator Console (Dispatcher),
  • Diagnostic Application Software

 (These applications are not supported in direct mode operation)