Abstract: An incident in which a radio LAN device cannot determine a reception signal to be a radio LAN signal frequently occurs even though the transmitted signal is a radio LAN signal, due to collisions between the radio LAN signals or other causes. In other words, the radio LAN device operates in such a manner in some case as to protect a reception signal with a threshold for Energy Detection even in a case where the stated reception signal is a radio LAN signal, so that appropriate protection is not carried out. Because an incident in which a radio LAN signal is protected with a threshold for Energy Detection frequently occurs, the threshold for Energy Detection is adjusted to preferably protect the radio LAN signals.

Abstract: Provided is a base-station device, a terminal device, a transmission method, and a reception method that realize efficient transmission in a radio communication system that performs large-scale MU-MIMO transmission. The base-station device having a plurality of antennas and performing communication with a plurality of terminal devices simultaneously, includes a channel state information acquisition unit for acquiring channel state information with respect to the plurality of terminal devices; a signal spreading unit for performing spreading and multiplexing for a plurality of signals addressed to each of the terminal devices by using a spread code in a spatial direction of each of the terminal devices; and a precoding unit for applying precoding to the signals, which have been spread and multiplexed, based on the channel state information.

Abstract: Provided are a terminal apparatus and a communication method that are able to improve communication quality and an acquisition rate of transmission opportunity in a communication system requiring carrier sense. The terminal apparatus of the invention includes a reception unit that receives a frame and changes a CCA method on the basis of information included in the frame. The CCA method includes a method of setting a CCA level as a value other than a predetermined value of the CCA level. The reception unit has a function of performing carrier sense and a method of changing the CCA level includes a method of setting a period in which the carrier sense is performed as a value other than a value of a predetermined carrier sense period.

Abstract: A terminal apparatus that communicates with a base station apparatus includes: a higher layer on which NAICS information is configured from the base station apparatus; and a control unit that, in a case where the NAICS information has been configured, determines the number of layers, antenna port numbers, and scrambling identities of a signal addressed to the terminal apparatus and an interfering signal. The terminal apparatus further includes a receiving unit that receives downlink control information, and the control unit determines at least one of the number of layers, antenna port number, and scrambling identity of the interfering signal on the basis of the downlink control information.

Abstract: In an LTE-A system, there is a problem that it is difficult to perform stable communication in a case where there is a time when another system occupies an unlicensed band being used. There is provided a base station apparatus that communicates with a terminal device in a second frequency band different from a first frequency band capable of being used as a dedicated frequency band. The base station apparatus includes: a CS determination unit that performs carrier sense in a subframe of carrier sense configured in the second frequency band; a synchronization signal generation unit that generates a synchronization signal; and a wireless transmission unit that transmits the synchronization signal. In a case where the CS determination unit determines that another system does not perform communication in the second frequency band, the wireless transmission unit transmits the synchronization signal generated by the synchronization signal generation unit.

Abstract: A decrease in access rate to a wireless medium caused by an exposed terminal apparatus is improved. A wireless communication apparatus of the present invention includes a reception unit that receives a frame indicating start of a medium protection operation, and acquires, from the frame indicating the start of the medium protection operation, BSS identification information for identifying a BSS to which a transmission-source wireless communication apparatus of the frame indicating the start of the medium protection operation belongs, and a transmission unit that determines whether or not to start a transmission operation of a frame addressed to another wireless communication apparatus belonging to a BSS to which the wireless communication apparatus belongs based on the BSS identification information.

Abstract: A BSS to which a destination wireless communication apparatus of a physical layer frame belongs is identified, and accuracy of preamble detection is improved by changing a reception operation. A wireless communication apparatus includes a reception unit that detects a frame including information for identifying a BSS, and a control unit that switches between a first operation in a case where the frame is a frame which is associated with a BSS to which the wireless communication apparatus belongs and a second operation in a case where the frame is a frame which is not associated with the BSS to which the wireless communication apparatus belongs. Carrier sensing is not performed in the first operation, and the carrier sensing is performed in the second operation.

Abstract: A BSS to which a destination wireless communication apparatus of a physical layer frame belongs is identified, and accuracy of preamble detection is improved by changing a reception operation. A wireless communication apparatus includes a reception unit that detects a frame including information for identifying a BSS, and a control unit that switches between a first operation in a case where the frame is a frame which is associated with a BSS to which the wireless communication apparatus belongs and a second operation in a case where the frame is a frame which is not associated with the BSS to which the wireless communication apparatus belongs. An NAV corresponding to a first period is configured in the first operation.

Abstract: A method that carries out uplink multiple access while reducing complexity in processing accompanying exchange of control information. A terminal device that performs uplink multiple access communication includes a reception unit that receives a frame including uplink multiple access connection information, a first autonomous decentralized control unit that instructs securing time of a wireless resource, and a second autonomous decentralized control unit that instructs securing time of a wireless resource after reception of a frame including the uplink multiple access connection information. The terminal device is instructed securing time of the wireless resource by the first autonomous decentralized control unit in a case that a frame including the uplink multiple access connection information is not received. Securing time of the wireless resource is instructed by the second autonomous decentralized control unit in a case that a frame including the uplink multiple access connection information is received.

Abstract: A base station apparatus, a terminal apparatus, and a communication method that make it possible to achieve reduction in delay of communication are provided. A base station apparatus of the present invention is a base station apparatus for performing communication with a terminal apparatus under a first communication scheme or a second communication scheme. The first and second communication schemes differs in allowable delay time from each other. The base station apparatus notifies the terminal apparatus of pre-scheduling information including information indicating a plurality of resource candidates that are used in the first communication scheme. The base station apparatus enters a receiving operation of the first communication scheme in a resource indicated by the plurality of resource candidates.

Abstract: It is intended to provide a transmission device, a reception device and a communication system capable of improving transmission characteristics by performing packet combining by HARQ in MU-MIMO transmission using non-linear precoding. In a case of receiving NAK from any of terminal devices (400), a base station device (100) retransmits a packet, in which an error occurs, addressed to this terminal device. The base station device (100) transmits the data to be retransmitted together with other transmission data addressed to a different terminal device or addressed to the own terminal device by spatial multiplexing transmission with MU-MIMO. At this time, for the retransmission data, precoding is performed such that a perturbation term same as a perturbation term which has been added to this data by non-linear precoding at the time of initial transmission is added.

Abstract: A terminal device is intended to reduce a decrease in reception performance in response to inter-cell interference and inter-user interference even when multiple interference streams are received. The terminal device connected with a first base station apparatus receives a first interference signal serving as inter-user interference from the first base station apparatus, and a second interference signal serving as inter-cell interference from a second base station apparatus, demodulates at least one interference stream of the first interference signal using terminal information transmitted from the first base station, and suppresses the second interference signal using a reception weight.

Abstract: There are provided a communication method, an authentication method, a terminal apparatus, a communication system, and an authentication apparatus for improving communication quality and a communication opportunity capture rate under an environment in which terminal apparatuses cluster within a two-dimensionally narrow range. The communication method of this invention is a communication method for providing a communication service associated with a principal service to a terminal apparatus, including a step of providing the communication service on the basis of information on the principal service provided to the terminal apparatus. The information on the principal service provided to the terminal apparatus is a grade of the principal service.

Abstract: A signal that is transmitted to a terminal apparatus itself is demodulated with high precision, and throughput is improved. A terminal apparatus that communicates with a base station apparatus includes: a reception unit that receives downlink control information from the base station apparatus; and a signal detection unit that demodulates a signal that is transmitted to the terminal apparatus itself, based on first modulation mapping, and demodulates an interference signal based on second modulation mapping, in a case where information relating to a transmit power of the interference signal is included in the downlink control information.

Abstract: A method that carries out uplink multiple access while reducing complexity in processing accompanying exchange of control information. A terminal device that performs uplink multiple access communication includes a reception unit that receives a frame including first uplink multiple access information, and a transmission unit that transmits a frame including second uplink multiple access information based on the frame including the first uplink multiple access information, and further, after standby of a predetermined period, initiates the uplink multiple access communication.

Abstract: Provided are a base station apparatus, a terminal apparatus, and a communication method, in all of which interference is reduced to improve throughput and to increase more opportunity for communication by each terminal apparatus.

Abstract: A signal that is transmitted to a terminal apparatus itself is demodulated with high precision, and throughput is improved. A terminal apparatus that communicates with a base station apparatus includes a signal detection unit that demodulates a signal that is transmitted to the terminal apparatus itself, based on first modulation mapping in a case where a predetermined transmission mode is configured, and that demodulates a signal based on second modulation mapping in a case where a transmission mode other than the predetermined transmission mode is configured.

Abstract: Provided are a radio transmission apparatus, a radio receiving apparatus, a radio communication system, and a communication method that make it possible for the radio transmission apparatus performing OFDMA transmission to highly efficiently determine a radio receiving apparatus that is caused to participate in the OFDMA transmission. The radio transmission apparatus that performs OFDMA transmission with a plurality of radio receiving apparatuses includes a reception unit that has a function of performing carrier sense and a function of receiving a function information response frame including function response information indicating that a function of performing the OFDMA transmission is included, and a transmission unit that has a function of switching whether or not to transmit a frame to at least one of the plurality of radio receiving apparatuses on a basis of the carrier sense.

Abstract: Communication is efficiently performed even when the communication is performed in a high carrier frequency. A terminal apparatus includes: a reception unit configured to receive assistance information from a primary cell and a plurality of synchronization signals from a secondary cell and to perform synchronization on the basis of the assistance information and the plurality of synchronization signals; and a transmission unit configured to transmit measurement information regarding at least one of the plurality of synchronization signals. The assistance information includes respective pieces of information regarding the plurality of synchronization signals. The assistance information includes an ID of each of the plurality of synchronization signals, and the terminal apparatus transmits the ID as the measurement information regarding the synchronization signal.

Abstract: In a transmission system in which data addressed to multiple terminal apparatuses is multiplexed, a preferable transmission frame that efficiently uses radio resources and that enables a transmission time of the frame to be reduced is constructed. A base station apparatus uses at least one of multiple radio resources to transmit a transmission frame to a terminal apparatus. The base station apparatus includes a physical-layer frame generating unit that divides the transmission frame addressed to the terminal apparatus into multiple transmission frames and that generates physical layer frames so that the transmission frames obtained through division are transmitted in multiple radio resources, and also includes a radio transmission unit that transmits the generated physical layer frames to the terminal apparatus in the multiple radio resources.