Abstract: A controller in a transceiver for radio communications in which the same frequency is shared between multiple communications systems is disclosed that includes: a cyclic autocorrelation value calculation part configured to calculate the cyclic autocorrelation value of a first one of the communications systems from a received signal; and a data transmission authorization part configured to determine whether to authorize data transmission in a second one of the communications systems based on the calculated cyclic autocorrelation value of the first one of the communications systems.

Abstract: A transmitter comprises a frequency utilization status detector configured to detect the utilization status of an allocated frequency band based on a received signal, a symbol placement determination unit configured to determine placement of pilot symbols based on the detected status of frequency utilization, and a symbol placement unit configured to place the pilot symbols according to the determined symbol placement.

Abstract: A transmitter used in the multiband environment includes a frequency allocation unit (106) configured to select and allocate a frequency band that satisfies a user QoS from among multiple separate frequency bands currently available for the user, a parameter determination unit (111) configured to determine a transmission parameter required for signal transmission based on the allocated frequency band, and a multi-user scheduling control unit (110) configured to determine a transmission schedule for multiple users taking into account the frequency bands allocated to the multiple users.

Abstract: When OFDM signals are transmitted from a plurality of antennas, a pilot carrier is transmitted from one antenna among the plurality of antennas, and a null signal is transmitted from an antenna other than that antenna by a subcarrier of the frequency band that transmits the pilot carrier.

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 radio communication control device includes a radio parameter update determination portion, a transmission power value change portion and a radio parameter update portion. The radio parameter update determination portion determines whether or not to update a radio parameter relating to at least one of a communication frequency and transmission power to a new radio parameter. The transmission power value change portion performs a transmission power change process to change a transmission power value during data transmission to a radio communication station to a smaller value in stages at predetermined intervals when the radio parameter update determination portion determines to update the radio parameter to the new radio parameter. A radio parameter update portion updates the radio parameter to the new radio parameter when the transmission power value change portion changes the transmission power value to a preset lower limit or less.

Abstract: A base station that communicates with a mobile station includes: a storing unit for storing a predetermined number of base station information, each including a base station ID for discriminating a specific base station and parameter information for radio communications set for the specific base station; an acquisition unit for acquiring a base station ID of other base stations forming a destination cell of the mobile station, or a base station ID of other base station forming a source cell of the mobile station; an aggregating unit for aggregating the number of times that each of the base station IDs is acquired in a first time period; a determination unit for determining a priority of each of the base station IDs on the basis of the aggregated results of the acquisition numbers; a judging unit for judging whether or not there is a base station ID which has a priority higher than the base station ID stored in the storage, and whose acquisition number is larger than a predetermined number of times; and a mana

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: A wireless communications system is disclosed. The wireless communications system includes a base station unit that is provided in a predetermined area and that is configured to perform wireless communications with at least one mobile station; and at least one measurement unit that is provided in the predetermined area and that is configured to communicate with the base station unit. The measurement unit includes: a unit configured to receive at least a common control channel transmitted from the base station unit; a unit configured to measure a wireless channel status; and a unit configured to report a measurement result to the base station unit. In the wireless communications system, the base station unit adjusts a downlink wireless parameter according to the measurement result reported from the measurement unit.

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: An OFDM signal communication system used in broadband mobile communication, achieves stable operation under severe frequency selective fading environments, giving high quality. The OFDM signal communication system which transmits OFDM signals over the same radio frequency from N transmitting antennas, has an inverse matrix computer for computing an N×N inverse matrix constituted by propagation coefficients for respective propagation paths between each of N transmitting antennas and each of N receiving antennas, and a subcarrier demodulator which separates the signals of the respective propagation paths, based on the obtained inverse matrix.

Abstract: To automatically set up temporarily the parameters required for radio communication, based on the parameters acquired from another base station apparatus existing in the neighborhood. A pair of base station identifier and down scrambling code reported from a base station apparatus in the neighborhood is acquired. The non-overlapping down scrambling code is set to a newly established base station apparatus based on the acquired contents. Whether or not the base station apparatus is located in the neighborhood is judged according to at least one of the Hop number and the required arrival time on a communication path up to the base station apparatus.

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 wireless control apparatus is disclosed that forms and controls an area of a base station according to an antenna pattern. The wireless control apparatus includes an area formation information gathering part that gathers area formation information pertaining to area formation of a neighboring base station; and an antenna pattern control part that controls and directs at least one of a main lobe, a side lobe, and a null point between the main lobe and the side lobe of the antenna pattern based on the area formation information to reduce frequency interference between a current cell formed by a current base station and a neighboring cell formed by the neighboring base station.

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.

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

Abstract: A controller in a transceiver for radio communications in which the same frequency is shared between multiple communications systems is disclosed that includes: a cyclic autocorrelation value calculation part configured to calculate the cyclic autocorrelation value of a first one of the communications systems from a received signal; and a data transmission authorization part configured to determine whether to authorize data transmission in a second one of the communications systems based on the calculated cyclic autocorrelation value of the first one of the communications systems.

Abstract: A wireless resource assigning apparatus for assigning wireless resources to transmission data of a plurality of users is disclosed. The wireless resource assigning apparatus includes a scheduling part configured to start scheduling for all users from a first wireless resource among a plurality of wireless resources prioritized according to a predetermined criterion, and repeat scheduling up to the last wireless resource for users except for users to whom any wireless resource has been assigned.

Abstract: A transmitter comprises a frequency utilization status detector configured to detect the utilization status of an allocated frequency band based on a received signal, a symbol placement determination unit configured to determine placement of pilot symbols based on the detected status of frequency utilization, and a symbol placement unit configured to place the pilot symbols according to the determined symbol placement.