Kyocera Corporation

Tomoyoshi Yokota

Tomohiro Miki

Simon Armour

Joe McGeehan

Ying Peng

Masahiro Saito

Fangwei Tong

Mitsuhiro Kitaji

Hitoya Tachikawa

Atsushi Yamamoto

A communication terminal device and method operable to control a handover is disclosed. A connection is made to a first wireless communication network. If occurrence of a handover factor is detected, a search is made for a second wireless communication network based on a detection order, and handoff is made.

Wireless communication device and method for handover in wireless communication networks

A radio terminal () includes: an MIH user () for managing mobility from a first network to a second network; and an MIH function unit () for controlling handover from the first network to the second network. The MIH function unit () notifies a link control unit () of a condition setting request including a first judgment local formula as a condition for starting setting of the second network and the radio link and a second judgment logical formula as a condition executing a handover from the first network to the second network. The first judgment logical formula and the second judgment logical formula indicates a combination of threshold values to be satisfied by a plurality of radio parameters in the first network and the established radio link.

Radio terminal, information processing device, information processing program, and information processing method

A radio terminal () comprises a radio communication unit () that receives packets via a first or second network at predetermined intervals; a buffer () that temporarily stores packets received by a receiving unit; a radio communication unit () that transmits a preparation request for a handover from the first network to the second network; and an application processing unit () that reproduces the packets stored in the buffer () at a rate that is established in accordance with the predetermined intervals. The application processing unit () changes a packet reproduction rate to a rate slower than the predetermined rate in response to transmission of the preparation request for handover, thereby increases the amount of packets stored in the buffer.

Radio terminal and communication terminal

A wireless communication device () comprising a first communication portion () that connects to a wide-area wireless communication network; a second communication portion () that connects to a narrow-area wireless communication network; and processing portions () that, during communication with a wide-area wireless communication network via the first communication portion (), upon detection of a communication area boundary vicinity of the wide-area wireless communication network when communication is performed, perform processing so that the second communication portion () continues performing communication that the first communication portion () is performing.

Wireless communication device continuously performing communication and method thereof

A communication system includes a call control server that receives a call request containing preference information of the outgoing call side, calls the incoming call side and transmits call request reception information containing information indicating that the call request has been received and the preference information to a message transmission server in order to convey the received call request to the incoming call side. The message transmission server receives the call request reception information transmitted from the call control server and transmits an activation message for activating communication with the outgoing call side containing the preference information contained in the call request reception information, based on the received call request reception information, to the incoming call side.

Communication system, wireless communication terminal, communication method, wireless communication method, wireless communication apparatus and control method thereof

A switching serverdetermines whether or not to switch a network for an uplink from a radio IP networkA to a radio IP networkB, on the basis of an acquired communication quality of the uplink. In addition, when determining to switch the network for the uplink to the radio IP networkB, the switching servertransmits, to an MN, an uplink switching instruction to switch the network for the uplink to the radio IP networkB.

Communication control device, radio communication device, communication control method and radio communication method

A radio terminalincludes a radio communication unitconfigured to receive packets at predetermined intervals through a first networkor a second network, a bufferconfigured to temporarily store packets received by the radio communication unit, another radio communication unitconfigured to transmit a preparation request for handover from the first networkto the second network, and an application processorconfigured to reproduce the packets stored in the bufferat a predetermined rate determined according to the predetermined interval. The application processorstops the adaptive buffer control in response to the transmission of the handover preparation request.

A radio terminal () includes an MIH user () configured to manage mobility from the first network to the second network; and an MIH function unit () configured to control a handover from the first network to the second network. The MIH user () notifies a link controller () via the MIH function unit () of a condition setting request including a first judgment logical formula being a condition to start an establishment of a radio link with the second network and a second judgment logical formula being a condition to execute a handover from the first network to the second network. The first judgment logical formula and the second judgment logical formula each indicate a combination of thresholds to be satisfied by a plurality of respective link is parameters in the radio link established with the first network.

A radio terminalincludes a radio communication unitconfigured to receive packets at predetermined intervals through a first networkor a second network, a bufferconfigured to temporarily store packets received by the radio communication unit, another radio communication unitconfigured to transmit a preparation request requesting a preparation of handover from the first networkto the second network, and an application processorconfigured to reproduce the packets stored in the bufferat a predetermined rate determined according to the predetermined interval. The application processordecreases the amount of the packets stored in the bufferby changing a packet reproducing rate to a rate higher than the predetermined rate in response to the transmission of the preparation request.

In a radio communication system employing HARQ scheme wherein the maximum number of slots is changed, a radio terminal () which calculates a predictive transmission rate being the predictive value of a downlink transmission rate at a future time after the receiving time of a downlink radio signal is provided with a storage unit (A) which stores in association with a DRC a corrected transmission rate obtained by causing a defined transmission rate being a downlink transmission rate in the case of using all the maximum number of slots to reflect the probability of succeeding in decoding data using only some of the slots, and a calculation unit () which predicts the reception quality at the future time on the basis of the reception quality before the receiving time, obtains from the storage unit (A) the corrected transmission rate associated with the DRC corresponding to the predicted reception quality, and calculates the predictive transmission rate from the obtained corrected transmission rate.

Radio terminal and transmission rate prediction method

When communication quality exceeds the first threshold, the radio communication terminalstarts connection with the radio communication systemand establishes the radio link Lto the radio communication system. Further, a handover from the radio link Lto the radio link Lis performed when the communication quality exceeds the second threshold after the establishment of the radio link L, the second threshold corresponding to communication quality degraded than that indicated by the first threshold.

Radio communication device and radio communication method

It is judged whether a mobile nodeexists at a boundary A overlapped with a different sector of the base station for use in communication or at a boundary B overlapped with an area of another base station or at an area fringe C. In accordance with the application in use and the results thus judged, a handover is performed between base stations in a wireless communication system, or switching to the another wireless communication system is made, or simultaneous communication with the another wireless communication system is performed, or either the uplink or the downlink is switched to the another wireless communication system.

Wireless communication terminal and method of controlling the same

VoIP packets as many as the number transmittable within a time period equal to a window Tminus a window Tare transmitted to a radio IP networkA in a case where the bandwidth of the radio IP networkA is determined to be of a size not capable of transferring VoIP packets within a predetermined delay time period. In addition, a remaining number of VoIP packets excluding the number of VoIP packets transmittable within the time period equal to the window Tminus the window Tare transmitted to a radio IP networkB.

Communication device, radio communication device, communication control method and radio communication method

An EV-DO terminal module is made up of hardware and software for implementing the function as an EV-DO terminal. A W-LAN terminal module is made up of hardware and software for implementing the function as an AP of W-LAN. An information exchange terminal module has a function equal to that of the W-LAN terminal module. A control module has a dialup function and a function based on PPP protocol and is a hardware and software module for controlling the EV-DO terminal module, the information exchange terminal module, and the W-LAN terminal module.

Communication control apparatus determining terminal connection

A video streaming client () transmits an MIH_Get_Service_Quality.request which requests a report about service quality which is used in the video streaming client () at regular intervals to an MIHF (Media Independent Handover Function) (). When the MIHF () acquires the MIH_Get_Service_Quality.request, on the basis of the communication quality of a radio link which is notified from a link control unit (), the MIHF () calculates a prediction value of the service quality in the future in the regular intervals and notifies the video streaming client () of the calculated prediction value by an MIH_Get_Service_Quality.response.

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Yokohama, Japan

Tomoyoshi Yokota