Cooperative relaying selection method applicable to broadband cluster system

The invention discloses a cooperative relaying selection method applicable to a broadband cluster system. The cooperative relaying selection method is different from traditional algorithms, electric quantity information of users is added, and two short time slots are added in a two-time-slot data transmission mode. After a first short time slot base station emits data information, successful users are enabled to broadcast service information. After failure users receive the service information, the failure users select an expected relay according to the electric quantity information. Failure users of a second short time slot broadcast the expected relaying information. When the expected relaying information received by the successful users conforms to self information, the expected relaying information is added into a relay transmission assembly and used as a relay to forward multicast information. According to a communication system, the aim that the best relay is selected when a plurality of relays commonly