Abstract: A communication terminal includes a first wireless unit for carrying out cellular communication, and a second wireless unit for carrying out WLAN communication. A control unit carries out a power save operation that inactivates the WLAN communication function of these wireless communication functions. Location information for access points accessible by WLAN communication is stored in the storage unit. The control unit calculates distances between access points and the communication terminal and determines whether or not the communication terminal is within communication range of any of the access points by matching location information for the communication terminal obtained by the GPS unit and location information for the access points stored in the storage unit. When the access point is within communication range, the control unit gives notification by outputting the signal strength via a display unit and the like according to the distance to the access point.

Abstract: A combination of antennas to be used is selected based on a distance between a plurality of antennas or the polarization direction of a radio signal to be transmitted/received.

Abstract: A combination of antennas to be used is selected based on a distance between a plurality of antennas or the polarization direction of a radio signal to be transmitted/received.

Abstract: Provided is a communication system capable of enhancing convenience for remotely operating a movable-body-mounted apparatus mountable in a movable body such as a vehicle. For example, a communication system includes a movable-body-mounted apparatus including: a movable body information storage part which stores movable body information including a received signal quality of a radio wave used for communication to/from a center server and information on a vehicle; a separation determination part which determines whether or not a user who moves along with the vehicle is separated from the vehicle; and a movable body information notification part which notifies the user of the movable body information stored in the movable body information storage part when the separation determination part determines that the user is separated from the vehicle.

Abstract: When a terminal-status detecting unit detects a predetermined terminal status with communication over a first mobile communication system being enabled by a first mobile communication unit, a control unit causes a second mobile communication system to start a process of acquiring a second mobile communication system to set communication via the second mobile communication system in an enabled status.

Abstract: A power transmitting device includes a power transmitter (21) transmitting electric power in a contactless manner, a data communicator (22) obtaining identification information of at least one power receiving device that has become possible to receive electric power transmitted from the power transmitter (21), a power receiving device finding/separation detector (261) counting a number of state switchings between a power unreceivable state and the power receivable state during a predetermined period of time, for each power receiving device of which identification information has been obtained, and a power transmission controller (263) controlling electric power transmission performed by the power transmitter (21), on the basis of the number of state switchings counted by the power receiving device finding/separation detector (261).

Abstract: A power transmitting device transmitting electric power to a power receiving device includes a power transmitter (110) transmitting electric power in a contactless manner at a resonant frequency having a predetermined relation with a resonant frequency of a part, the part being provided in the power receiving device and receiving electric power, a data receiver (112) receiving from the power receiving device a random number value generated by the power receiving device each time electric power transmission of the power transmitter (110) is started, and a controller (117) determining whether or not all random number values satisfy predetermined condition. When the condition is satisfied, the controller (117) continues electric power transmission via the power transmitter (110).

Abstract: In a mobile communication terminal, a communication control section controls communication on the basis of a selected radio communication system or frequency band and manages the state of communication. A signal-strength-indicator acquiring and storing section acquires signal-strength indicators and stores it. A communication-state acquiring section acquires the state of communication. A signal-strength-indication displaying control section determines whether a radio communication system or a frequency band is being searched for from the communication state. When it is being searched for, antenna bars indicative of signal strength are not shown or flashed when the signal-strength indicator is indicated on a display section.

Abstract: An electronic apparatus includes a plurality of communication units including a first communication unit which communicates via a first communication network and a second communication unit which communicates via a second communication network. The electronic apparatus acquires presence information indicating a communication state of a communication apparatus from a presence server managing a communication state of a communication apparatus on a communication network, via at least one communication network. The electronic apparatus acquires presence information of an alternative communication apparatus being as a communication apparatus which communicates via the second communication network in place of the second communication unit included in itself. The electronic apparatus determines as to whether the alternate communication apparatus is in an online state, based on the acquired presence information.

Abstract: A communication terminal optimally switches between the use of multicast reception and unicast reception, in consideration of the mobile radio environment of each terminal. For example, received signal strength indicator information is acquired at a received signal strength indicator information acquisition time calculated using a content reception time. Either multicast reception or unicast reception is selected according to the acquired received signal strength indicator information and content reception is performed. An optimal reception system can be selected and reception failure can be reduced. In addition, by performing a dynamic switching of reception methods as such, the base station-end can perform multicast delivery rather than unicast delivery when possible to communication terminals in favorable mobile radio environments, thereby significantly reducing the traffic load placed on communication paths.

Abstract: When a communication apparatus (server device) that includes wireless access means and can send content data by using the wireless access means starts sending content data, it calculates a communication band that remains available for the server device to perform communication, so that any content that has a rate equal to or greater than the remaining communication band may not be publicized open to and may not hence be sent to a client device.

Abstract: A communication terminal optimally switches between the use of multicast reception and unicast reception, in consideration of the mobile radio environment of each terminal. For example, received signal strength indicator information is acquired at a received signal strength indicator information acquisition time calculated using a content reception time. Either multicast reception or unicast reception is selected according to the acquired received signal strength indicator information and content reception is performed. An optimal reception system can be selected and reception failure can be reduced. In addition, by performing a dynamic switching of reception methods as such, the base station-end can perform multicast delivery rather than unicast delivery when possible to communication terminals in favorable mobile radio environments, thereby significantly reducing the traffic load placed on communication paths.

Abstract: A communication terminal has a plurality of wireless communication units. An access control unit determines whether or not a selected wireless interface is in a state where a connection request is possible based on communication state information on the wireless interface selected beforehand in the plurality of wireless interfaces. When determining that a connection request using the selected wireless interface is not possible, the access control unit determines whether or not to change over the wireless interface used for a communication based on a changeover availability information table set beforehand. When determining that a changeover of the wireless interface is not possible, the access control unit idles without performing a connection request to establish a communication until it is determined that a connection request through the selected wireless interface becomes possible.

Abstract: When a communication apparatus (server device) that includes wireless access means and can send content data by using the wireless access means starts sending content data, it calculates a communication band that remains available for the server device to perform communication, so that any content that has a rate equal to or greater than the remaining communication band may not be publicized open to and may not hence be sent to a client device.

Abstract: A communication terminal optimally switches between the use of multicast reception and unicast reception, in consideration of the mobile radio environment of each terminal. For example, received signal strength indicator information is acquired at a received signal strength indicator information acquisition time calculated using a content reception time. Either multicast reception or unicast reception is selected according to the acquired received signal strength indicator information and content reception is performed. An optimal reception system can be selected and reception failure can be reduced. In addition, by performing a dynamic switching of reception methods as such, the base station-end can perform multicast delivery rather than unicast delivery when possible to communication terminals in favorable mobile radio environments, thereby significantly reducing the traffic load placed on communication paths.

Abstract: An electronic apparatus includes a plurality of communication units including a first communication unit which communicates via a first communication network and a second communication unit which communicates via a second communication network. The electronic apparatus acquires presence information indicating a communication state of a communication apparatus from a presence server managing a communication state of a communication apparatus on a communication network, via at least one communication network. The electronic apparatus acquires presence information of an alternative communication apparatus being as a communication apparatus which communicates via the second communication network in place of the second communication unit included in itself. The electronic apparatus determines as to whether the alternate communication apparatus is in an online state, based on the acquired presence information.

Abstract: A communication terminal optimally switches between the use of multicast reception and unicast reception, in consideration of the mobile radio environment of each terminal. For example, received signal strength indicator information is acquired at a received signal strength indicator information acquisition time calculated using a content reception time. Either multicast reception or unicast reception is selected according to the acquired received signal strength indicator information and content reception is performed. An optimal reception system can be selected and reception failure can be reduced. In addition, by performing a dynamic switching of reception methods as such, the base station-end can perform multicast delivery rather than unicast delivery when possible to communication terminals in favorable mobile radio environments, thereby significantly reducing the traffic load placed on communication paths.

Abstract: A communication system has a communication terminal and information processing device that can be mounted on a movable body. The information processing device includes a request transmission part that transmits to a communication terminal within a predetermined range a request signal, the request signal requesting the transmission of an image, through broadcast communication for transmitting information to a plurality of transmitting partners. The request signal contains a positional information indicative of a position. The communication terminal includes: an image shooting part that shoots an image around the communication terminal; a position acquisition part that obtains a position at which the image is shot; a recording part that associates and records the shot image and the position; and a receiving part that receives the request signal; and an image transmission part that transmits an image.

Abstract: A communication terminal optimally switches between the use of multicast reception and unicast reception, in consideration of the mobile radio environment of each terminal. For example, received signal strength indicator information is acquired at a received signal strength indicator information acquisition time calculated using a content reception time. Either multicast reception or unicast reception is selected according to the acquired received signal strength indicator information and content reception is performed. An optimal reception system can be selected and reception failure can be reduced. In addition, by performing a dynamic switching of reception methods as such, the base station-end can perform multicast delivery rather than unicast delivery when possible to communication terminals in favorable mobile radio environments, thereby significantly reducing the traffic load placed on communication paths.

Abstract: An electronic apparatus comprises a plurality of communication units including a first communication unit which communicates via a first communication network and a second communication unit which communicates via a second communication network. The electronic apparatus acquires presence information indicating a communication state of a communication apparatus from a presence server managing a communication state of a communication apparatus on a communication network, via at least one communication network. The electronic apparatus acquires presence information of an alternative communication apparatus being as a communication apparatus which communicates via the second communication network in place of the second communication unit included in itself. The electronic apparatus determines as to whether the alternate communication apparatus is in an online state, based on the acquired presence information.