A control unit is selected from a plurality of narrowband mobile stations also forming an ad-hoc network. The control unit is configured to control and manage a narrowband trunking operation via the ad-hoc network. The control unit receives a call request over a narrowband control channel from a first mobile station, assigns a pair of narrowband traffic channels for a call associated with the call request, chooses two mobile stations from the plurality of mobile stations to act as a narrowband repeater for the call, the pair including a respective receiver mobile station and a respective transmitter mobile station, informs the repeater mobile stations of the assignment and of the assigned traffic channels for the call, and grants the call request over the narrowband control channel. The grant includes an indication of the assigned traffic channels on which the repeater mobile stations can be located for the call.