Maintenance of group call in mobile communication system

Mobile station and method comprises a mobile communication system for network infrastructure and a subscriber group calling, wherein the method comprises the following steps: Is a group calling to call, the first speeds first, participates to the mobile station for implementing group calling called a voice communication method, a frame structure comprises a voice transmission one of a mobile and time slot of the voice wherein one for. The method, a first speeds distribution time slot or a time (204), only and first mobile station may send a signalling message to electrically connected with the network infrastructure in the time groove or a times; To the first mobile station and third speeds data transmission indication, only and first mobile station may send a signalling message to powering network infrastructure's time slot or a time (204); The third speeds of allocating (204) does not transmitter and signalling message to the first stroke then time slot or a time.