Abstract: A wireless communication method including: transmitting first information from a second wireless terminal to a wireless base station, the first information relating to a first wireless quality from a first wireless terminal to the second wireless terminal, the first wireless quality being measured based on a first reference signal transmitted from the first wireless terminal, the wireless base station being configured to determine whether to perform device-to-device communication between the first wireless terminal and the second wireless terminal, and transmitting second information from the first wireless terminal to the wireless base station, the second information relating to a second wireless quality from the second wireless terminal to the first wireless terminal, the second wireless quality being measured based on a second reference signal transmitted from the second wireless terminal.

Abstract: A communication system includes a first communication terminal and a second communication terminal that performs direct communication with the first communication terminal. The first communication terminal controls transmission power of a second reference signal which is a partial reference signal among a plurality of reference signals so as to reach known transmission power, the plurality of reference signals being transmitted with first data and used for demodulating the first data, controls transmission power of a first reference signal which is another reference signal other than the second reference signal among the plurality of reference signals so as to reach transmission power linked to transmission power of the first data, and transmits the plurality of reference signals subjected to transmission power control to the second communication terminal.

Abstract: A base station which is able to perform radio communications with a relay station and a mobile station, the base station includes a transmitter configured to transmit radio signals to the relay station in downlink backhaul subframes, and to limit transmission of radio signals to the relay station in subframes other than the downlink backhaul subframes; and a controller configured to allow, when performing a random access procedure to the relay station, the transmitter to transmit a message of the random access procedure even in the subframes other than the downlink backhaul subframes.

Abstract: When a plurality of radio signals having different sub frame lengths are transmitted on the same radio carrier, a radio signal of a short sub frame length is arranged inside a carrier band, and a radio signal of a sub frame length longer than the sub frame length of the short sub frame length signal is arranged outside the carrier band.

Abstract: A base station accommodated in a communications system for communicating with a mobile station, the base station includes: a transmitter configured to generate frequency band information indicating which frequency band of frequency bands used in the communications system to communicate with a mobile station, to transmit the frequency band information by using a specific frequency band selected from a plurality of frequency bands available in the system, and to communicate with the mobile station using at least one of the plurality of frequency bands.

Abstract: A wireless terminal, includes a first transceiver configured to transmit a first type of wireless signal; and a second transceiver configured to transmit a second type of wireless signal; wherein the first transceiver is configured to transmit an indication of interference when interference is detected between the first type of wireless signal and the second type of wireless signal and to transmit information showing a condition of each of the first and second types of wireless signal with the indication of interference; and the first transceiver is further configured to receive interference control information useable by the terminal in mitigating the detected interference.

Abstract: A wireless communication system includes a plurality of wireless stations including a first wireless station, a second wireless station, and a third wireless station. The wireless communication system further includes a first controller that obtains a transmission timing at which the third wireless station transmits first notification information to the second wireless station, the first notification information indicating that the third wireless station is to communicate with the second wireless station; and a first communicator that transmits second notification information to the second wireless station at the obtained transmission timing, the second notification information indicating that the first wireless station is to directly communicate with the second wireless station.

Abstract: A radio communication apparatus specifies a radio resource area in which a radio communication apparatus searches for a control signal, on the basis of information about the use of a plurality of frequency bands. Then, the radio communication apparatus transmits a control signal addressed to the radio communication apparatus in the specified radio resource area. The radio communication apparatus calculates the specified radio resource area on the basis of the information about the use of the plurality of frequency bands. Then, the radio communication apparatus searches signals in the calculated radio resource area, out of signals received from the radio communication apparatus, and thereby detects the control signal addressed to the radio communication apparatus.

Abstract: A first radio communication device includes: a control unit that, when a second radio communication device is currently connected to the first radio communication device, notifies radio communication devices other than the first radio communication device of information on the second radio communication device; and a transmission unit that transmits, to the second radio communication device, information on the radio communication devices which have been notified of the information on the second radio communication device. The second radio communication device includes a transmission unit that selects, on the basis of the information on the radio communication devices which has been transmitted from the transmission unit of the first radio communication device, one of the radio communication devices and transmits to the selected radio communication device a control signal for controlling handover.

Abstract: A wireless terminal, includes: an antenna; and, a processor, coupled to the antenna, the processor to receive, through the antenna, a common reference signal transmitted from a base station at a first timing at a frequency which is selected in accordance with identification information of a cell, to receive, through the antenna, a wireless-terminal-specific reference signal and a control signal both of which are concurrently transmitted by the base station at different frequencies, at a second timing that is different from the first timing; and, to demodulate the received control signal, based on the received wireless-terminal-specific reference signal.

Abstract: A relay station which performs radio communications with a base station and a mobile station, the relay station includes: a receiver configured to receive radio signals from the base station in downlink backhaul subframes, and to limit reception of radio signals from the base station in subframes other than the downlink backhaul subframes; and a controller configured to allow, when performing a random access to the base station, the receiver to receive a message of the random access even in the subframes other than the downlink backhaul subframes.

Abstract: A base station accommodated in a communications system for communicating with a mobile station, the base station includes: a transmitter configured to generate frequency band information indicating which frequency band of used frequency bands available in the communication system is to be used for transmission of data information with a mobile station, to transmit the frequency band information by using a specific frequency band assigned from the used frequency bands, and to transmit data information by using at least one of the frequency bands; wherein the frequency bands except for the specific frequency band, are made variable.

Abstract: A communication apparatus that performs receiving processing of data transmitted at timings of a predetermined interval, the communication apparatus includes: a transmitting unit configured to transmit a signal indicating that data is successfully received when the data transmitted at Mth timing according to the predetermined interval is successfully received; and a control unit configured to determine whether or not a retransmission control processing is performed when the signal indicating that the data is successfully received is transmitted, wherein the control unit transmits a signal indicating that the data is successfully received when the retransmission control processing is performed.

Abstract: A reordering method of sending packets, to which numbers indicating the packet order are added, to a mobile station from a base station, and rearranging the order of the packets at the mobile station, this includes forwarding from a source base station to a target base station, packets, not sent to the mobile station before a handover sequence, or packets, a confirmation response of proper reception has not been received from the mobile station, transmitting preferentially those packets from the target base station to the mobile base station and then transmitting packets received from a host station to the mobile station, giving packets information indicating that the packets are jump packets when transmitting the packets to the mobile station, received from the host station with the order jumped, deciding jump packets are not objects of reordering, and performing the reordering process for packets that are objects of reordering.

Abstract: A radio communication apparatus to perform communication with another radio communication apparatus by using a plurality of frequency bands, the radio communication apparatus includes, a receiving unit configured to receive, when performing a random access procedure to said another radio communication apparatus, a control message by using a first frequency band as a response to a preamble message transmitted by the radio communication apparatus, the control message instructing communication using a second frequency band different from the first frequency band; and a control unit configured to perform, when the control message corresponds to the preamble message, data communication with said another radio communication apparatus by using the second frequency band.

Abstract: A transmitting apparatus is capable of transmitting data at a first frequency and second frequency to a receiving apparatus. A transmitter of the transmitting apparatus transmits a predetermined wideband signal, in a first time period in a frequency band which does not include the first frequency and in a second time period in a frequency band which does not include the second frequency. A quality measuring unit of the receiving apparatus measures the quality of communication with the transmitting apparatus based on the wideband signal received in the first and second time periods.

Abstract: A coil component is provided with first wire and second wires that are wound around a winding core. nth turns of the first and second wires are wound around a surface of the winding core in this order in parallel and form a first winding layer. Each of n+1th and subsequent turns of the second wire is wound around the surface of the winding core so as to be parallel to a previous turn of the second wire and form the first winding layer. Each of n+1th and subsequent turns of the first wire is wound on the first winding layer so as to be fitted into a valley of the first winding layer formed by the same and previous turns of the second wire and form a second winding layer. The same turns of the first and second wires are adjacent to each other at each turn.

Abstract: A first radio communication apparatus transmits first and second control signals to a second communication apparatus. The first control signal carries information to be used in communication performed with a first frequency band. The second control signal carries information to be used in communication performed with a second frequency band. The second radio communication apparatus detects these first and second control signals by attempting signal extraction from received signals with common candidates for control signal length. The first radio communication apparatus controls whether to use one frequency band or more than one frequency band to transmit the first and second control signals, based on bandwidths of the first and second frequency bands.

Abstract: In conditions of low data traffic, such as during the night, when transmitting pilots in a downlink radio transmission zone, sub frames are divided into (1) first sub frames that transmit common pilots over a whole transmission band, and (2) second sub frames that transmit common pilots over a specified narrow band of a whole transmission band, where first sub frames are transmitted at a specified period, and second sub frames are transmitted for period of time except the specified period.

Abstract: A radio communication apparatus that performs communication with another radio communication apparatus by using a plurality of pairs of a downlink frequency band and an uplink frequency band, the apparatus includes: a receiving unit configured to receive a control message by using a downlink frequency band of a first pair among downlink frequency bands of the pairs during a random access procedure to said another radio communication apparatus, the control message including identification information indicating use of an uplink frequency band of a second pair different from the first pair, the downlink frequency band of the first pair being monitored for control messages by the radio communication apparatus; and a control unit configured to control the radio communication apparatus to perform data communication with said another radio communication apparatus by using the uplink frequency band of the second pair indicated by the identification information included in the control message.