Nippon Telegraph and Telephone Corporation

Nippon Telegraph Telephone Corporation

Masato Mizoguchi

Riichi Kudo

Takeo Ichikawa

Yasushi Takatori

Koichi Ishihara

Yusuke Asai

Shoko Shinohara

Munehiro Matsui

Tomoki Murakami

Yasuhiko Inoue

Hirantha Abeysekera

Etsushi Yamazaki

Yutaka Miyamoto

Takayuki Kobayashi

Akihide Sano

Tadao Nakagawa

Eiji Yoshida

Akira Kishida

Junichi Iwatani

Tomoaki Kumagai

Shogo Yamanaka

Masahiro Morikura

Akira Yamada

Hideyuki Nosaka

Yoshifumi Morihiro

Tomoyuki Yamada

Kentaro Nishimori

Takefumi Hiraguri

Takeshi Onizawa

Takahiro Asai

Yukihiko Okumura

Yoshiaki Kisaka

Masahito Tomizawa

Seiji Okamoto

Hayato Fukuzono

Yasufumi Morioka

Kengo Horikoshi

Tomoyoshi Kataoka

Hiroto Yasuda

Eiichi Yamada

Akiyoshi Inoki

Mamoru Akimoto

Wenjie Jiang

Tetsu Sakata

Daisuke Koizumi

Hirantha Sithira Abeysekera

A format that includes a BSSID of a transmitting station within a preamble of the frame is an HE format, and a format that does not include a BSSID within the preamble but includes a BSSID in a MAC header is a Non-HE format; and a wireless station in the BSS includes a control part which checks a format of a frame received at a predetermined receiver sensitivity or above, and continues demodulation of the received frame if the format is HE format and the BSSID in the received frame is consistent with its own BSS, and stops the demodulation of the received frame if the HE format and the BSSID in the received frame is not consistent with its own BSS.

Wireless communication system and wireless communication method

Provided is a wireless communication system in which, based on a random access scheme, a transmission opportunity (TXOP) acquired by a wireless access point is granted to a wireless station when performing uplink data transmission from the wireless station to the wireless access point and the TXOP acquired by the wireless station is granted to the wireless access point when performing downlink data transmission from the wireless access point to the wireless station, the system includes a scheduling unit for TXOP granting determining one or more wireless stations having a quality of an uplink data transmission lower than a prescribed value as TXOP responders to which the wireless access point grants the TXOP, and determining one or more wireless stations having a quality of a downlink data transmission lower than the prescribed value as TXOP holders which grant the TXOP to the wireless access point.

Interference in preamble signals and pilot signals in cooperative transmission using interference suppressing technology is avoided. A wireless apparatus for transmitting a wireless signal on which directivity control has been performed to stations in a wireless system including at least one wireless apparatus is provided with a known signal generating unit which generates a known signal to be added to the wireless signal, a weighting processing unit which performs weighting on the known signal generated by the known signal generating unit, and a wireless processing unit which transmits the known signal on which the weighting has been performed by the weighting processing unit.

Wireless signal transmitting method and wireless apparatus

A predetermined STA includes a station information collection unit collecting from the STA itself and other STAs station information used for selection of STAs performing simultaneous transmission and for control of the simultaneous transmission, and a simultaneous-transmission request unit knowing occurrence of a QoS data frame based on the station information and transmitting a request frame requesting the simultaneous transmission to an AP. The AP includes a station information collection unit; a simultaneous-transmission determination unit selecting a combination of the STAs performing the simultaneous transmission based on the station information by reception of the request frame; and a trigger transmission unit transmitting to each of the STAs performing the simultaneous transmission a trigger frame instructing to performs the simultaneous transmission and including information necessary for controlling the simultaneous transmission. Each of the STAs designated by the trigger frame is configured to simultaneously transmit the wireless frames to the AP.

Wireless communication system, wireless communication method, wireless LAN access point, and wireless LAN station

Provided is a wireless communication system in which a plurality of basic service sets (BSSs) performing wireless transmission from a transmitting station to a destination station by performing access control based on CSMA/CA exist adjacent to each other, and in which wireless communication is performed by controlling a CCA threshold considering an interference power value between each BSS that uses the same channel, in which the transmitting station includes a control block determining the CCA threshold value according to the interference power value of the BSS considered as an interference source, calculating a SINR in the destination station according to the interference power value, determining a MCS which is a combination of a modulation scheme and a code rate according to the SINR, and performing the access control based on the CSMA/CA.

A wireless user equipment performing wireless communication in a primary and a secondary frequency bands, a first wireless access point AP performing the wireless communication in the primary frequency band, and a second wireless base transceiver station BTS performing the wireless communication in the secondary frequency band are included. The AP and the BTS are connected to each other through a network. A UD report transfer unit transfers a UD report including information relating to transmission-waiting user data destined for a receiving node. The receiving node includes a transmission opportunity control unit which sets a fixed transmission prohibition time in a channel in the primary frequency band for a wireless communication device in a vicinity, obtains a transmission opportunity, grants the transmission opportunity to the transmitting node, and causes the user data to be transmitted from the transmitting node according to the transferred UD report.

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Yokosuka, Japan

Masato Mizoguchi