Patent application number | Description | Published |
20110090120 | RADIO COMMUNICATION DEVICE AND ARRIVAL DIRECTION ESTIMATION METHOD - A receiver having an array antenna estimates arrival directions of multiple paths that arrive with an angular spread. Consequently, arrival direction estimation accuracy can be ensured without increasing throughput even if the power every path is low by estimating an average arrival direction of an entire set of multiple paths having the angular spread from a result of one angular spectrum by multiple correlation operation units that perform mutual correlation operations with pilot signals for baseband signals received by the array antenna, a path detection unit that detects multiple arrival path receiving timings by generating a delay profile based on output of each of the correlation operation units, a path correlation value synthesis unit that synthesizes a correlation operation value calculated in the multiple correlation operation units and an arrival direction estimation unit that collectively estimates multiple path arrival directions using output of the path correlation value synthesis unit. | 04-21-2011 |
20110090813 | RADIO COMMUNICATION DEVICE AND ARRIVAL DIRECTION ESTIMATION METHOD - A receiver having an array antenna estimates arrival directions of multiple paths that arrive with an angular spread. Consequently, arrival direction estimation accuracy can be ensured without increasing throughput even if the power every path is low by estimating an average arrival direction of an entire set of multiple paths having the angular spread from a result of one angular spectrum by multiple correlation operation units that perform mutual correlation operations with pilot signals for baseband signals received by the array antenna, a path detection unit that detects multiple arrival path receiving timings by generating a delay profile based on output of each of the correlation operation units, a path correlation value synthesis unit that synthesizes a correlation operation value calculated in the multiple correlation operation units and an arrival direction estimation unit that collectively estimates multiple path arrival directions using output of the path correlation value synthesis unit. | 04-21-2011 |
20130188654 | FRAME TRANSMISSION SYSTEM - A frame transmission system includes a frame transmitter and a frame receiver. The frame transmitter includes a frame fragmentation unit and a reproduction header appending unit. The frame fragmentation unit fragments an input frame and outputs transfer frames when the length of the input frame exceeds a predetermined fragmentation reference frame length, and does not fragment the input frame and outputs the input frame as a transfer frame when the length of the input frame is less than or equal to the fragmentation reference frame length. The reproduction header appending unit appends a reproduction header to the transfer frames outputted from the frame fragmentation unit. Here, the reproduction header being required when the transfer frames are reproduced at a receiving side. The reproduction header appending unit varies the header length of the reproduction header to be appended to the transfer frame, according to the length of the input frame. | 07-25-2013 |
Patent application number | Description | Published |
20100118745 | WIRELESS COMMUNICATION APPARATUS - In a wireless communication apparatus adopting a time division duplex system for executing transmission and reception using a plurality of antennas, deviation of amplitude and phase occurring between transmission and reception circuits is detected and corrected using a communication signal. Channel estimation means 105 detects channel information based on reception output of reception circuits 104-1 to 104-N provided in a one-to-one correspondence with a plurality of antennas 101-1 to 101-N. Correction value detection means 110 finds a correction value for correcting deviation occurring between each of transmission circuits 103-1 to 103-N and each of the reception circuits 104-1 to 104-N based on the channel information. A wireless communication apparatus 100 transmits an already known signal (training signal) to a base station with which the wireless communication apparatus conducts communications. The base station executes channel estimation based on the already known signal and generates and transmits a correction signal (probe signal). The correction value detection means 110 of the wireless communication apparatus 100 detects the correction value using the correction signal (probe signal). | 05-13-2010 |
20100120379 | MIMO COMMUNICATION DEVICE - Provided is a MIMO communication device which can maintain the MIMO communication characteristic at a certain level regardless of the device installation position. The MIMO communication device ( | 05-13-2010 |
20100159842 | WIRELESS DISTANCE MEASUREMENT SYSTEM AND WIRELESS DISTANCE MEASUREMENT METHOD - A wireless distance measurement system and a wireless distance measurement method that measure the distance between a base station and a terminal without clock synchronization between a plurality of base stations, and without requiring input of the position relationships between a plurality of base stations. Clock phase shift section ( | 06-24-2010 |
20100167758 | RADIO POSITIONING SYSTEM AND COORDINATE CONFIGURING METHOD - A radio positioning system includes a plurality of base stations and a radio terminal. Each of the base stations includes a reference signal generating portion which generates a reference signal for positioning, a transmission portion which transmits the reference signal, a reception portion which receives a signal from its outside, a positioning portion which calculates a position relative to the radio terminal or base station as a signal sender based on the received signal, and a reference signal return portion which receives a reference signal transmitted from another base station and returns the reference signal to the another base station. The radio terminal includes a terminal reception portion which receives the reference signal, and a terminal transmission portion which returns the received reference signal. A reference signal transmitted by a first base station of the base stations is received and returned by the reference signal return portion in a second base station, the returned reference signal is received by the reception portion in the first base station, and the positioning portion in the first base station measures a position relative to the second base station based on the received reference signal. | 07-01-2010 |
20100183063 | Wireless Distance Measurement System and Wireless Terminal - A wireless distance measurement system and wireless terminal improve the accuracy of distance measurement when the UWB communication scheme is used. In wireless terminal | 07-22-2010 |
20110133988 | RADIO ARRIVAL DIRECTION ESTIMATION DEVICE AND RADIO ARRIVAL DIRECTION ESTIMATION METHOD - A radio arrival direction estimation device that accurately estimates the arrival direction of radio waves from a desired tag, even when there are multiple antennas disposed at short intervals. When ID detection timing is provided from a timing detector ( | 06-09-2011 |
20110140970 | BASE STATION DEVICE AND DISTANCE MEASURING METHOD - Provided are a distance measuring device and a distance measuring method which can easily distinguish a reflected signal from a desired tag from an unnecessary wave so as to improve the distance measuring accuracy even when IR-UWB is used for measuring a distance. The method uses a reader ID indicated by a code string formed by P bits (P is a natural number) for identifying a base station and a tag ID indicated by a code string formed by Q bits (Q is a natural number) for identifying a radio terminal. The method generates a unique word containing P pulses, each of which is ON/OFF-modulated depending on whether each of P bits indicating the reader ID is 1 or 0. The method generates a frame containing 2 M unique words and a burst containing Q frames. The method further outputs a transmission signal containing a plurality of bursts. A radio terminal ASK-modulates the transmission signal depending on whether each of the Q bits indicating the tag ID is 1 or 0. The ASK-modulated signal is sampling-received at timings of different phases by 1/M (M is an integer not smaller than 1) of the transmission clock cycle. | 06-16-2011 |
20110181471 | ADAPTIVE ANTENNA RADIO COMMUNICATION DEVICE - A device for estimating a direction-of-arrival of a radio wave, the device comprising an array antenna including a plurality of antenna elements for receiving a high frequency signal, a demultiplexer for demultiplexing the received high frequency signal for each of the plurality of antenna elements to generate a plurality of frequency component signals and a direction estimating unit for estimating the direction-of-arrival of the radio wave by using two or more of the plurality of frequency component signals which are contiguous in a frequency direction. | 07-28-2011 |
20120014412 | POSITIONING SYSTEM AND POSITIONING METHOD - A positioning system and a positioning method which suppress the occurrence of jitter to improve positioning accuracy. A base station ( | 01-19-2012 |
20120032850 | ARRAY SIGNAL PROCESSING DEVICE - Provided is an array signal processing device capable of, when a spatial averaging method is applied to array signal processing, reducing the number of antennas constituting an array antenna while making use of the spatial averaging method. In the array signal processing device ( | 02-09-2012 |
20120044974 | RADIO TERMINAL DEVICE, RADIO BASE STATION DEVICE, RADIO RANGING SYSTEM, AND RADIO RANGING METHOD - Disclosed are a radio terminal device and the like, which achieve an improvement in the accuracy of ranging between a UWB reader and a UWB tag regardless of whether an active method or a semi-passive method. In a terminal ( | 02-23-2012 |
20120213131 | WIRELESS COMMUNICATION APPARATUS - Wireless communication apparatus adopting a time division duplex system for transmission and reception using plural antennas, deviation of amplitude and phase occurring between transmission and reception circuits is detected and corrected using a communication signal. Channel estimation means detects channel information based on reception output of N reception circuits having a one-to-one correspondence with N antennas. Correction value detection means finds a correction value for correcting deviation occurring between each of N transmission circuits and each of the N reception circuits based on the channel information. A wireless communication apparatus transmits an already known signal (training signal) to a base station with which the wireless communication apparatus conducts communications. The base station executes channel estimation based on the already known signal and generates and transmits a correction signal (probe signal). The correction value detection means of the wireless communication apparatus detects the correction value using the correction signal. | 08-23-2012 |