Brief Answer
DMR increases capacity by dividing a 12.5 kHz channel into two time slots. This allows for example, two conversation groups to run in parallel through the same repeater. In practice, however, usable capacity depends on group structure, conversation discipline, emergency calls, data traffic, repeater locations, and system planning.
The term time slot sounds technical but is central to planning DMR radio networks.
The Principle
DMR uses TDMA. A radio channel is temporally divided: Time slot 1 and time slot 2 can carry different groups, calls, or services.
What Counts for Capacity
- Number of users and conversation density.
- Groups and priorities.
- Repeater locations and coverage.
- Emergency calls, data, GPS, and status messages.
- Radio discipline and clear calling groups.
Typical Errors
The theoretical two time slots are understood as unlimited capacity. In real networks, conversation traffic must be planned and monitored.
FAQ
How many conversations can DMR conduct on one channel?
Typically, two simultaneous conversations or services over two time slots.
Does DMR require a repeater for this?
The capacity advantages are particularly relevant in repeater and system operation.
What happens with too many users?
Calls wait, groups block each other, or important communication becomes difficult.
How is DMR capacity planned?
Based on user numbers, roles, groups, locations, traffic load, and priorities.
Sources and Current Status
This page was created on July 6, 2026. Technical and regulatory information must be cross-checked with current manufacturer data, standards, frequency regulations, and site conditions in specific projects.