Reducing the impact of interference on a control channel

In a digital wireless communication system, a first control channel is replicated 104 into a plurality of control channels when jamming or interference on the first control channel is detected 102. Wireless communication units operating on the first control channel switch 118 to different replicated control channels. Information about the available replicated control channels may be transmitted 106 over a broadcast control channel and stored 108 in a memory of each communication unit. When the interference on the first control channel disappears, all the communication units may switch back to the first control channel so that the replicated control channels may be closed 124. Hence, the effect of interference may be minimised by distributing communication units over different control channels because jamming of all control channels is difficult and jamming of one channel affects fewer of the communication units.