To provide a communication system for a system wirelessly metering meters that can surely recognize the patterns of a start signal with high speed of response.

In the case of starting a No.2 wireless slave set among a plurality of (No.1-n) wireless slave sets, first a wireless master set continues transmission of an identification signal denoting the No.2 wireless slave set, in addition to a synchronizing signals as a recognition pattern (synchronizing signal +'2'). N-sets of the wireless slave sets execute the reception processing by intermittent operations with a prescribed pause period for power saving. For example, each wireless slave set is started every 2 seconds and executes reception processing of FSK data in 10 milliseconds. In this case, the No.2 wireless slave set discriminates whether the recognition pattern sent from the master set is matches with its own recognition pattern for the 10 milliseconds and when they match, the system is started and enters a communication mode. Since the wireless slave set can be identified with the recognition pattern signal of the 10 milliseconds, power consumption can considerably reduced more than that of conventional system.