TETRA Direct Mode solution is offered as encrypted or non- encrypted for users;
- Demanding usage in a limited area
- Instead of requirements of wide coverage area, central management needs to communicate over a single base station,
- Have high number of user groups and the calling frequency,
- It is necessary to use TDMA (Time-Division Multiple Access) because it is important to efficiently allocate the frequency in the region where the communication occurs,
- Generally, who are in need of communication in city centers
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 only by the caller initiating a call. When the number of time slots is increased, the number of calls that can be performed on the same physical channel increases. Since the TETRA communication protocol has 4 time slot TDMA structure, four different calls can be made in the same physical channel, thus ensuring frequency efficiency.
If the communication needs of users change and a more advanced solution is required:
In addition to base stations installed for TETRA Direct Mode, the installation of different base stations,
Establishing a system management centre,
Connecting the installed base stations to each other and to the switching unit in the system management centre,
Programming the radios according to the new architecture,
it is possible to switch to the TETRA Trunk Wide Area System configuration.