Abstract: A communication terminal used in a mobile communication system complying with a carrier sense multiple access scheme is disclosed. The communication terminal includes: a receiving unit configured to receive a wireless packet transmitted by another communication terminal or a base station; a determination unit configured to determine periodic transmission timing of the communication terminal based on determination criterion information included in the wireless packet; and a transmission unit configured to periodically transmit wireless packets to the base station based on the transmission timing.

Abstract: A communication terminal used in a mobile communication system complying with a carrier sense multiple access scheme is disclosed. The communication terminal includes: a receiving unit configured to receive a wireless packet transmitted by another communication terminal or a base station; a determination unit configured to determine periodic transmission timing of the communication terminal based on determination criterion information included in the wireless packet; and a transmission unit configured to periodically transmit wireless packets to the base station based on the transmission timing.

Abstract: A communication system which superposes and transfers a wireless multicarrier signal including a plurality of subcarriers is provided with: a transmitting device which performs allocation of predetermined data generated based on transmission data to both a non-superposed band which is a frequency band in which no interference signal is present and a superposed band which is a frequency band in which the interference signal is present, or to the non-superposed band while giving a higher priority to the non-superposed band, and generates and transmits the multicarrier signal based on the allocation; and a receiving device which receives the multicarrier signal transmitted from the transmitting device.

Abstract: In a wireless communication system including a transmitter device and a receiver device used for transmission of wireless signals having a plurality of sub-carriers, the transmitter device performs error correction coding on transmitting data and selects at least one of the plurality of sub-carriers used for transmission of error-correction coded data as a null sub-carrier having zero amplitude, thus transmitting the error-correction coded data, whilst the receiver device receives signals having the plurality of sub-carriers from the transmitter device so as to retrieve original transmitted data by implementing error correction decoding on received signals, thus determining whether an interference wave occurs in the sub-carrier upon detecting reception power exceeding a predetermined threshold in the sub-carrier serving as the null sub-carrier.

Abstract: In a communication system configured by a transmitting station device and a receiving station device for transmitting and receiving a multicarrier signal using a spectrum including a plurality of subcarriers, a superposed rate which is a rate in which a superposed band in which interference is occurring is used in a used frequency band used for transmitting the multicarrier signal is set so as to increase frequency utilization efficiency of the used frequency band, and the multicarrier signal is transmitted using a spectrum allocated in accordance with the set superposed rate.

Abstract: It is possible to reduce the effect of an interference signal while suppressing increases in a circuit scale and a processing time. A reception device receives a multicarrier signal and an interference signal via a radio transmission path, detects a frequency position of the interference signal, performs filtering to suppress the multicarrier signal and the interference signal at the detected frequency position of the interference signal, removes a guard interval from the multicarrier signal suppressed by the filtering, demodulates each subcarrier of the multicarrier signal from which the guard interval is removed, and performs error correction on the demodulated signal.

Abstract: In a multicarrier wireless communication system adopting forward error correction codes, a reception method adapted to a receiver 1 receiving wireless signals is constituted of an interference band detection process for selecting a sub-carrier having low reliability among a plurality of sub-carriers of desired waves as a specific sub-carrier, a weight coefficient generation process for generating weight coefficients for reducing reliability in sub-carriers with respect to the selected specific sub-carrier, a demodulation process for demodulating received wireless signals of sub-carriers, a weighted calculation process for performing weighted calculation applying weight coefficients to demodulated values of sub-carriers of wireless signals, and a decoding process for performing a decoding process for error correction on values calculated of sub-carriers.

Abstract: In a mobile communication system, multiple transceivers perform radio communications in the same frequency band.

Abstract: A directivity control system includes a first reception station device which receives an interference signal and a desired signal; a cooperative station device disposed at a different place from the first reception station device, which receives a signal using an antenna; and a control device which controls the directivity of an antenna of the first reception station device, wherein the control device regards a combination of the antenna of the first reception station device and the antenna of the cooperative station device as one array antenna, and calculates a sum, using a weight, of a received signal received using the antenna of the first reception station device and a received signal received using the antenna of the cooperative station device to compose a directivity pattern having a null in an arrival direction of the interference signal in the array antenna.

Abstract: An interference cancelling station ICS includes a transmission weight factor calculating unit calculating a transmission weight factor w2 and an interference cancelling data signal transmitting unit generating an interference cancelling data signal by multiplying, by the transmission weight factor w2, a data signal transmitted by a base station BSb of the wireless communication system B and transmitting the interference cancelling data signal in synchronization with timing with which the base station BSb of a wireless communication system B transmits the data signal, and a mobile station MSa of a wireless communication system A receives a data signal transmitted by a base station BSa of the wireless communication system A, the data signal having cancelled interference from the base station BSb of the wireless communication system B.

Abstract: A frequency band allocation device is disclosed. The frequency band allocation device comprises a frequency band selection unit (1161, 1162) for selecting usable frequency bands from a dedicated frequency band, a registered frequency band and an unlicensed frequency band; and a frequency band allocation unit (1163) for allocating a frequency band out of the selected usable frequency bands to an uplink and downlink, so as to satisfy user required QoS.

Abstract: A communication control device is provided which efficiently utilizes wireless resources to improve communication quality and system throughput by appropriately setting and performing node transmission power.

Abstract: A base station and method of communication of a base station is provided. The base station includes a storage configured to store a predetermined number of base station information, each including a base station ID, an acquisition unit configured to acquire base station IDs, an aggregating unit configured to aggregate a number of times that each of the base station IDs is acquired, and a determination unit configured to determine a priority of each of the base station IDs. The base station also includes a judging unit configured to judge whether or not there is a base station ID having a priority higher than the base station ID stored in the storage, and a manager configured to delete from the storage, and store in the storage, base station information including a base station ID.

Abstract: A communication terminal used in a mobile communication system complying with a carrier sense multiple access scheme is disclosed. The communication terminal includes: a receiving unit configured to receive a wireless packet transmitted by another communication terminal or a base station; a determination unit configured to determine periodic transmission timing of the communication terminal based on determination criterion information included in the wireless packet; and a transmission unit configured to periodically transmit wireless packets to the base station based on the transmission timing.

Abstract: A wireless communication device that performs packet transmission in accordance with a packet transmission system that performs wireless bandwidth allocation by virtual carrier sensing has a time-point management section that manages the time-point and outputs current time-point information, and a parameter management section that manages a parameter relating to packet transmission right acquisition priority.

Abstract: A communication terminal used in a mobile communication system complying with a carrier sense multiple access scheme is disclosed. The communication terminal includes: a receiving unit configured to receive a wireless packet transmitted by another communication terminal or a base station; a determination unit configured to determine periodic transmission timing of the communication terminal based on determination criterion information included in the wireless packet; and a transmission unit configured to periodically transmit wireless packets to the base station based on the transmission timing.

Abstract: Disclosed is a radio base station including: a common control channel transmission unit configured to transmit a common control channel by using radio communications parameter to be assigned to each radio base station; a transmission level determination unit configured to transmit the common control channel according to a predetermined transmission pattern; a reception level supervision unit configured to acquire a reception level of the common control channel received by a mobile station; and an overlap determination unit configured to determine whether or not the predetermined radio communications parameter overlaps with a radio communications parameter used in a different radio base station based on the reception level acquired by the reception level supervision unit and the predetermined transmission pattern.

Abstract: To provide a base station apparatus that can automatically update the parameters required for radio communication. A pair of identifier for identifying the self station and radio communication parameter is notified to another base station existing in the neighborhood of the self station, and the path loss value between another base station and a mobile station and the pair of identifier and radio communication parameter for another base station is acquired. The pair of identifier and radio communication parameter reported by the self station is set and updated, based on this acquired information. Since it is updated in consideration of the path loss value reported from the mobile station, the parameter can be updated at higher precision.

Abstract: A frequency band allocation device is disclosed. The frequency band allocation device comprises a frequency band selection unit for selecting usable frequency bands from a dedicated frequency band, a registered frequency band and an unlicensed frequency band; and a frequency band allocation unit for allocating a frequency band out of the selected usable frequency bands to a user, so as to satisfy user required QoS and maximize system frequency utilization factor.

Abstract: An OFDM receiver includes a timing error detection unit that determines error information based on a difference between receiving timing of a desired signal from a counterpart transmitter and receiving timing of an undesired signal from a non-counterpart transmitter. The timing error detection unit includes a pilot signal detection unit configured to detect a pilot signal of the desired signal and a pilot signal of the undesired signal from an FFT-processed received signal; a first converting unit configured to convert a frequency-domain channel estimate derived from the pilot signal of the desired signal to a first time-domain channel impulse response; a second converting unit configured to convert a frequency-domain channel estimate derived from the pilot signal of the undesired signal to a second time-domain channel impulse response; and an error information determination unit configured to determine the error information based on the first and second channel impulse responses.