Communications system

Abstract

When communications between mobile terminals MS 1 and MS 2 are terminated, a TRAU 1 judges whether the communications between mobile terminals MS 1 and MS 2 are synchronous and notifies the mobile terminal MS 1 of this information through both a base station control center BSC 1 and a base station BTS. The mobile terminal MS 1 stores this information in relation to both the dial number of the mobile terminal MS 2 and a voice-encoding type used in communications with the mobile terminal MS 2. Similarly, a TRAU 2 transmits the same information to the mobile terminal MS 2 and the mobile terminal MS 2 stores this information along with the dial number of the mobile terminal MS 1 and a voice-encoding type. When the mobile terminals MS 1 and MS 2 communicate the second time, communications are conducted using another voice-encoding type if the communications are asynchronous and using the previous voice-encoding type if the communications are synchronous, based on the information stored in this way.

1 . A communications terminal that corresponds to a plurality of voice-encoding types, comprising: 
 a storage unit storing information of at least one voice-encoding type out of the plurality of voice-encoding types in relation to identification information of the communications terminal, which is an opposite party; and    a transmitting unit transmitting the information of at least one voice-encoding type stored in relation to the communications terminal, which is an opposite party, to the network in communications.    
   
   
       2 . A communications system, comprising: 
 a function to designate a voice-encoding type to be used for each communications terminal to communicate and to perform control so that communications between the terminals can be conducted without using an encoding/decoding function of a transcoder in a network if voice-encoding types to be used by the communications terminals to communicate are the same; and    a notification unit notifying at least one of the communications terminals of control information if communications are or have been controlled without using an inter-communications terminal encoding/decoding function.