Abstract: The positional relationship between a master terminal and a slave terminal and the positional relationship of the slave terminal with the master terminal and with other slave terminals are measured, and a slave terminal subject to switching to master terminal is selected using the positional relationship. A network is then reconstructed with the slave terminal subject to switching selected in this manner as the new master terminal, and as a result the terminals forming the network prior to switching are prevented from falling outside of the communication range of the new master terminal and short range radio communication is maintained with the same terminals as those prior to switching.

Abstract: A radio apparatus which conducts radio communication by establishing a communication link with a given device includes a first store unit configured to store first identifying information which identifies the given device with which the communication link has been established, a receive unit configured to receive a connection request from another device when the communication link is disconnected; a obtain unit configured to obtain second identifying information which identifies the another device from the another device from which the connection request is received, a determine unit configured to determine whether the first identifying information agrees with the second identifying information, a establish unit configured to establish a communication link with the another device from which the connection request has been received, if it is determined that the first identifying information agrees with the second identifying information.

Abstract: A portable communication terminal which can establish communications between portable communication terminals by Bluetooth or the like by a simple operation are provided. An initiator terminal activates a short-distance radio communication section to make a Bluetooth function active and sends a request to start communications using a Bluetooth communication function to an acceptor terminal through a general communications network such as a telephone network or the like. The acceptor terminal makes the Bluetooth communication function active when it responds to the communication-starting request and sends a Bluetooth connection request to the initiator terminal by using the Bluetooth communication function. The initiator terminal responds to the Bluetooth connection request whereby a Bluetooth connecting session is established.

Abstract: A radio apparatus, to be used as a first ending node of a communication network, is connectable to a hands-free apparatus by a local radio link to form a hands-free system. A call made on the hands-free apparatus for an second ending node in the communication network is sent to the radio apparatus through a control channel on the local radio link. The radio apparatus and the hands-free apparatus arrange a voice channel to be established on the local radio link. The call is then sent to the second ending node. In a case where no voice channel is established within a predetermined time period after arranging the voice channel, the radio apparatus cancels the call to prevent a connection between the radio apparatus and the second ending node from being kept and charged.

Abstract: A radio apparatus which conducts radio communication by establishing a communication link with a given device includes a first store unit configured to store first identifying information which identifies the given device with which the communication link has been established, a receive unit configured to receive a connection request from another device when the communication link is disconnected; a obtain unit configured to obtain second identifying information which identifies the another device from the another device from which the connection request is received, a determine unit configured to determine whether the first identifying information agrees with the second identifying information, a establish unit configured to establish a communication link with the another device from which the connection request has been received, if it is determined that the first identifying information agrees with the second identifying information.

Abstract: With a conventional hands-free system formed by a radio apparatus and a hands-free apparatus connectable to each other by a local radio link, accepting a call on the hands-free apparatus is ineffective after the radio apparatus starts to send a reply message. There is provided a method for hands-free control to solve this problem. The method comprises measuring time since transferring a call arrived at the radio apparatus to the hands-free apparatus, and establishing a voice channel on the local radio link in a case where an operation is done to accept the call on the hands-free apparatus while the reply message is being sent.

Abstract: A channel disconnection detecting unit detects whether a voice channel is disconnected by an AG or by an HF. When the voice channel is disconnected by the AG, an AG control unit controls a modulation/demodulation unit to maintain a connection of the AG with a BS and a switching unit switches a voice signal to an AG speaker and an AG microphone. When the voice channel is disconnected by the HF, the AG control unit controls the modulation/demodulation unit to interrupt the connection of the AG with the BS.

Abstract: A portable communication terminal which can establish communications between portable communication terminals by Bluetooth or the like by a simple operation are provided. An initiator terminal activates a short-distance radio communication section to make a Bluetooth function active and sends a request to start communications using a Bluetooth communication function to an acceptor terminal through a general communications network such as a telephone network or the like. The acceptor terminal makes the Bluetooth communication function active when it responds to the communication-starting request and sends a Bluetooth connection request to the initiator terminal by using the Bluetooth communication function. The initiator terminal responds to the Bluetooth connection request whereby a Bluetooth connecting session is established.

Abstract: The positional relationship between a master terminal and a slave terminal and the positional relationship of the slave terminal with the master terminal and with other slave terminals are measured, and a slave terminal subject to switching to master terminal is selected using the positional relationship. A network is then reconstructed with the slave terminal subject to switching selected in this manner as the new master terminal, and as a result the terminals forming the network prior to switching are prevented from falling outside of the communication range of the new master terminal and short range radio communication is maintained with the same terminals as those prior to switching.