Abstract: Disclosed is a method for improving a communication success rate in a simultaneous call trial between subscribers in a mobile communication system. The method includes receiving by a second subscriber network an IAM message from a first subscriber network when a first subscriber tries a call to a second subscriber; determining by the second subscriber network whether the second subscriber has requested a termination to the first subscriber, after receiving the IAM; aborting by the second subscriber network an originating call trial of the second subscriber when the second subscriber has requested the termination; trying by the second subscriber network a page to the second subscriber after aborting the originating call trial; and setting a call between the first subscriber and the second subscriber by the first subscriber network and the second subscriber network, after succeeding in paging the second subscriber.

Abstract: Disclosed is a method for improving a communication success rate in a simultaneous call trial between subscribers in a mobile communication system. The method includes receiving by a second subscriber network an LAM message from a first subscriber network when a first subscriber tries a call to a second subscriber; determining by the second subscriber network whether the second subscriber has requested a termination to the first subscriber, after receiving the IAM; aborting by the second subscriber network an originating call trial of the second subscriber when the second subscriber has requested the termination; trying by the second subscriber network a page to the second subscriber after aborting the originating call trial; and setting a call between the first subscriber and the second subscriber by the first subscriber network and the second subscriber network, after succeeding in paging the second subscriber.

Abstract: Disclosed is a mobile communication system for handover between heterogeneous mobile communication networks. A dual-mode terminal has first and second modules capable of performing communication in first and second heterogeneous communication technologies, respectively. The dual-mode terminal measures strength of a signal received by the first module to determine whether the dual-mode terminal has moved between the mobile communication networks. If it is determined that the dual-mode terminal moves to a different network, the dual-mode terminal measures the strength of a signal transmitted from the different network, and converts measurement information into a first SMS message. A first mobile communication network device provides a service for performing communication with the first module, restores data from the first SMS message, and transmits the restored data to an interface network.