Which device controls and monitors all DMR RF communications?

• A. HMI
• B. ITU
• C. DMR
• D. C4I

Answer: (A)

The essential idea is centralized control and visibility over the DMR RF network. A C4I system—Command, Control, Communications, Computers, and Intelligence—provides the integrated framework to plan, route, monitor, and manage all communications across the network, including DMR radios. It brings together the hardware, software, and data needed to oversee link status, resource allocation, and policy enforcement, giving operators a single, coordinated picture of the entire communications picture.

An HMI is just the user interface that operators use to interact with such systems; it isn’t the central control and monitoring function by itself. ITU is the international regulatory body, not a device. DMR is the radio technology used for the actual transmission, but it doesn’t manage or monitor the network as a whole. So the device that controls and monitors all DMR RF communications is the C4I system.