| Patent application number | Description | Published |
|---|
| 20080279124 | OFDM WIRELESS COMMUNICATION METHOD AND WIRELESS COMMUNICATION APPARATUS - In a wireless communication system wherein at least two communication units employ the TDD wireless communication method based on OFDMA, an OFDM wireless communication method and a wireless communication apparatus are disclosed. The first communication unit transmits a pilot signal over the whole subband zone configured of divisions of a predetermined system band. The second communication unit having a plurality of antennas estimates a propagation path of the subchannels constituting continuous frequency blocks making up a subband from the pilot signal received. The second communication unit determines the array weight used at the time of signal transmission to the first communication unit using the estimation result. | 11-13-2008 |
| 20090210766 | WIRELESS COMMUNICATION SYSTEM, TERMINAL AND BASE STATION - A non-terminated packet is transmitted, by utilizing a spatial layer responded with an ACK, which is assumed as a released layer. Alternatively, a non-terminated packet is transmitted by using a released layer and an original spatial layer in combination. Alternatively, a new packet is transmitted in a released layer by utilizating time till termination of transmission of a non-terminated packet. A wireless communication system effectively utilizing a released layer, a terminal and a base station. | 08-20-2009 |
| 20090213743 | NOISE POWER ESTIMATION APPARATUS AND METHOD - A pilot signal is estimated by using the sampling theorem to estimate noise power in a stable manner without depending on the signal to noise ratio. A pilot signal estimation section obtains an estimated pilot signal by using the sampling theorem according to a plurality of received pilot signals sampled in the frequency domain by a sampling processor. A noise power estimation section estimates noise power by applying statistical averaging to the difference between the received pilot signal received from the sampling processor and the estimated pilot signal received from the pilot signal estimation section. | 08-27-2009 |
| 20090232236 | BASE STATION AND MOBILE STATION FOR OFDMA CELLULAR SYSTEM - In a cellular radio communication system, a base station or a mobile station has a TA (Time Alignment)-range-out detection function, so that when a TA-range-out state that is unable to compensate with a guard interval is detected, the transmission condition of an uplink signal at the mobile station is changed by the mobile station autonomously or by the base station and the mobile station cooperatively. | 09-17-2009 |
| 20090253461 | BASE STATION EQUIPMENT - A base station equipment determines, based on a specified condition, whether or not a wireless terminal exists in the vicinity thereof, and then if it exists in the vicinity, the base station equipment transmits information indicating that the base station equipment is ready to communicate with the wireless terminal. | 10-08-2009 |
| 20090300454 | TRANSMISSION APPARATUS, ACCESS POINT AND SYMBOL TRANSMISSION METHOD - In a transmission apparatus in a MIMO-OFDM communication system employing a cyclic diversity, a cyclic delay controller sets plural delay magnitudes different for respective antennas, in cyclic delayers for each predetermined timing. The cyclic delayers receive symbols subjected to orthogonal frequency division multiplexing, for the respective ones of plural allotted antennas. Besides, the cyclic delayers bestow cyclic delays on the individual symbols of the respective antennas in accordance with plural set delay magnitudes. The symbols cyclically delayed are outputted from the antennas. As the delay magnitudes, a first delay magnitude at a first transmission timing and a second delay magnitude at a second transmission timing are different for one antenna, and the delay magnitudes differ in the respective antennas for one transmission timing. Thus, in a MIMO-OFDM transmission scheme, a frequency diversity and a time diversity are enhanced to heighten a retransmission efficiency in a data retransmission mode. | 12-03-2009 |
| 20100046359 | Wireless Terminal, Base Station and Channel Characteristic Estimating Method - In a wireless communication system based on an OFDM access system, when forgetting averaging channel estimation is performed, there occurs a phase difference between a present channel estimated value and a past estimated value due to a change of FFT operation timing at a reception side. The error of the channel estimated value caused by the phase difference is corrected. A synchronization catching/tracking unit to determine an operation timing of an FFT from a received signal is provided, and an FFT operation timing difference acquisition section to grasp a change of the operation timing of the FFT generated by the synchronization catching/tracking unit is provided. Based on an FFT operation timing change amount as an output of the FFT operation timing difference acquisition section, a rotation operation is performed on a propagation path estimated result stored in a channel estimation section to estimate a propagation path from a received pilot signal, so that the error of the channel estimated value is corrected. | 02-25-2010 |
| 20100272018 | WIRELESS COMMUNICATION SYSTEM AND WIRELESS COMMUNICATION METHOD, AND BASE STATION APPARATUS - The present invention pertains to the technology for avoiding interference between adjacent frequencies occurring on cell boundaries or sector boundaries in a mobile wireless communication system using an OFDMA (Orthogonal Frequency Division Multiple Access) scheme. There are a single sector mode of no collaboration between sectors; a sector selection mode of collaborating between sectors to transmit with a specified frequency resource from only one sector, and a collaboration mode of collaborating between sectors to transmit signals from both sectors. Any of the three modes is selected on the basis of measurement results of RSRP (Reference Signal Received Power) reported from a mobile station. | 10-28-2010 |
| 20100290413 | RADIO BASE STATION APPARATUS - A DSP checks the traffic on a control channel transmitted to each terminal, and obtains a total of traffic on the control channel for each remote radio unit. The DSP transforms a correlation matrix calculated in an analysis section to a partial orthogonal matrix subjected to partial orthogonalization. The DSP divides one or more remote radio units into the groups in accordance with the sequence of rows or columns of the partial orthogonal matrix so that the total traffic for each group in which the total of traffic is added for one or more remote radio units within the group may be less than or equal to a predetermined threshold, and stores the identification number of the remote radio unit for each group in a memory. | 11-18-2010 |
| 20100322107 | WIRELESS COMMUNICATION NETWORK, METHOD OF GENERATING NEIGHBOR LIST IN THE WIRELESS COMMUNICATION NETWORK, AND CONTROL DEVICE THEREFOR - In a wireless communication system, a base station control device has following two steps on the basis of latitude/longitude information obtained from a GPS, that is, a first step of recognizing, from the positional information obtained from the GPS, the fact that base stations in new and old systems are installed at the same location, and a second step of linking a neighbor list of the old system to a neighbor list of the new system with use of the result of the first step. | 12-23-2010 |
| 20110038249 | TIMING ADJUSTMENT METHOD, RECEIVING STATION, AND TRANSMITTING STATION IN WIRELESS COMMUNICATION SYSTEM, AND WIRELESS COMMUNICATION SYSTEM - A discontinuous change in a transmission timing in a time domain, which is caused by a transmission timing adjustment processing of an OFDMA uplink or the like, brings about a discontinuous rotation of a signal phase in a frequency domain, resulting in reduced communication quality. A wireless communication system of the present invention allows the signal phase of the frequency domain in a receiving station to be continuous before and after the timing adjustment processings by controlling a signal sequence in a transmission signal after conversion in the time domain in synchronization with the timing adjustment processing. | 02-17-2011 |
| 20110085448 | WIRELESS COMMUNICATION SYSTEM, WIRELESS BASE STATION APPARATUS, AND WIRELESS COMMUNICATION METHOD - Random beams and FFR are used in combination, frequencies are grouped into a zone associated with the center of a cell and a zone associated with the border of the cell, and the random beams are applied only to the zone associated with the border of the cell. Since the number of resources to be allocated to the random beams decreases, a terminal lying on the border of the cell can reduce overhead. Using the zone associated with the center of the cell, beam scheduling can be freely performed within the cell. | 04-14-2011 |
| 20110092238 | WIRELESS COMMUNICATION SYSTEM, WIRELESS COMMUNICATION METHOD, AND BASE STATION - In a wireless communication system having a plurality of base stations and a control station controlling the plurality of base stations, the control station allocates, to the plurality of base stations, antenna patterns associated with directivity patterns for each of a plurality of frequency bands that can be utilized by the respective base stations and if it transmits, to respective ones of the plurality of base stations, parameters for associating the allocated antenna patterns with directivity patterns for each of the plurality of frequency bands; and the plurality of base stations associate the directivity patterns with the plurality of frequency bands on the basis of the parameters received from the control station and, in accordance with the associated directivity patterns, transmit signals to the antenna and receive signals from the antenna. | 04-21-2011 |
| 20110158187 | RADIO RESOURCE ASSIGNMENT METHOD AND BASE STATION DEVICE - A radio resource assignment method, wherein it is determined at a predetermined timing whether a cell is congested or not; the determination result is notified to adjacent base stations; results of determination of congestion or non-congestion received from adjacent base stations are stored; when it is determined that the base station is not congested, a check is made whether or not the adjacent base stations are congested; when the adjacent base stations are congested, the use of the resource blocks is restricted to decide an empty resource block; and information on the decided resource block is notified to the adjacent base stations. When it is determined that the base station is congested, the information on the empty resource blocks received from the adjacent base stations is checked, and the empty resource blocks are assigned to mobile terminal devices within the cell. | 06-30-2011 |
| 20110158190 | CELLULAR RADIO COMMUNICATION SYSTEM, RADIO BASE STATION APPARATUS AND RADIO TERMINAL UNIT - In a cellular radio communication system including of multi-antenna base stations, to make effective use of the reduced interference in supposing the use of beam form and avoid the interference in an adjacent station even if a space multiplex and the beam form are mixed. Frequencies intended for the cell edge in an FFR are classified into frequencies for space multiplex and a frequency for beam form. Thereby, a frequency at which the interference is reduced by the beam form is fixed. A frequency intended for the cell center is in a frequency band and signals are transmitted from three base stations. | 06-30-2011 |
