Fujitsu Corporation

Kensuke Sawada

Morihiko Minowa

Tokuro Kubo

Satoshi Nakamura

Noriyuki Kawaguchi

Dai Kimura

Kazuhisa Obuchi

Hiromasa Yamauchi

Kazuo Nagatani

Teruhisa Ninomiya

Koji Matsuyama

Kaoru Yokoo

Yoshihiko Asano

Kazumasa Ushiki

Mitsunori Fukazawa

Makoto Hamaminato

Akihiro Wada

Tokurou Kubo

An information processing apparatus includes a memory, and a processor coupled to the memory and configured to obtain location information indicating locations of a wireless transmitter and a wireless receiver, simulate a first power of a first reception signal at the wireless receiver in a condition that a radio signal is transmitted from the wireless transmitter, identify a first probability distribution model in accordance with the first reception signal, identify a first parameter of the first probability distribution model in accordance with the first power and a propagation environment defined by the locations of the wireless transmitter and the wireless receiver indicated by the location information, and based on the first probability distribution model using the first parameter, simulate a second power of a second reception signal at around the wireless receiver.

Information processing apparatus, method and non-transitory computer-readable storage medium

The mobile unit position detecting apparatus generates target data by extracting a target from an image shot by the image capturing device, extracts target setting data that best matches the target data, is prerecorded in a recording unit and is shot for each target, obtains a target ID corresponding to the extracted target setting data from the recording unit, detects position data associated with the obtained target ID, tracks the target in the image shot by the image capturing device, and calculates an aspect ratio of the target being tracked in the image. If the aspect ratio is equal to or lower than a threshold value, the mobile unit position detecting apparatus outputs the detected position data.

Mobile unit position detecting apparatus and mobile unit position detecting method

To provide an authentication technology making it compatible to facilitate inputting of authentication information and to ensure the security. An authentication device connected to a transmitting terminal and a receiving terminal via a communication line, receives a message from the transmitting terminal, receives authentication information from the transmitting terminal, registers the message in association with the authentication information, receives a request with a purport of acquiring the message from the receiving terminal, determines, based on the authentication information received from the receiving terminal and the registered authentication information, whether to authenticate or not, and, if authenticated, transmits the message to the receiving terminal.

Authentication system

A communication apparatus and method for channel switching for ad-hoc communication provides effective utilization of an infrastructure communication channel while preventing a deterioration in the quality of the infrastructure communication affected by a transmission signal used in the ad-hoc communication. Typically, the number of channels that can be used for a second communication is increased.

Mobile communication apparatus and channel switching method for ad-hoc communication

A mobile station enables communication with a fixed station and other mobile stations. The mobile station includes a receiving unit receiving first timing information, second timing information and reliability information with regard to the second timing information. A selector selects a timing, to be used for communication timing with the fixed station or the other mobile stations, between the first timing information and the second timing information based on the reliability information.

Mobile radio system and mobile radio control method

A digital baseband modulation apparatus includes: a spread modulation part for complex spreading an I component signal and a Q component signal of a send signal so as to output an output signal; and an amplitude conversion part for decreasing the amplitude component of the output signal to the half when the output signal is output on the I axis or on the Q axis.

Digital baseband modulation apparatus and demodulation apparatus

In a CDMA receiver for applying despread processing to direct wave or delayed waves that arrive via each path of multiple paths, applying synchronous detection processing to the despread signals obtained, combining the detection signals of respective paths and discriminating the received data on the basis of the combined signal, (1) a weighting unit provided for every path measures power of delayed received waves that arrive via its own path and, if the reception power is less than a set level (breakpoint level), subjects an output signal to weighting conforming to the reception power; (2) a RAKE combiner combines signals output from the weighting units of the respective paths; and (3) a data discrimination unit discriminates receive data based upon the output signal of the combiner.

CDMA receiver

An appearance of other mobile wireless station within a communication area of a second wireless communication system of a main mobile wireless station when the main mobile wireless station is in the communication area of a wireless base station of the first wireless communication system, is automatically detected. Communications with other mobile wireless station are autonomously started by a second wireless communication system and communications with the wireless base station are performed by the first wireless communication system. Communication content from the wireless base station of the first wireless communication system and communication content from the other mobile wireless station of the second wireless communication system are mutually relayed. The relay control is terminated when the other mobile wireless station moves outside the communication area of the second wireless communication system of the main mobile wireless station.

Mobile wireless terminal device

In a transmission power control apparatus for measuring SIR, which is a ratio of a receive signal to an interference signal, and controlling transmission power of a mobile station in such a manner that the measured SIR will agree with a target SIR, a fading detector detects the rate of change in fading, a correction unit corrects the target SIR based upon the rate of change in fading, and a transmission power control command creation unit creates a command for controlling transmission power of the mobile station in such a manner that the measured SIR will agree with the corrected target SIR, and transmits this command. Further, a searcher detects multipath and the levels of signals that arrive via respective ones of the paths, a level-difference calculation unit calculates level differences between the paths, a correction unit corrects the target SIR based upon the level differences between the paths, and a transmission power control command creation unit creates a command for controlling transmission power of the mobile station in such a manner that the measured SIR will agree with the corrected target SIR, and transmits this command.

Transmission power control apparatus

This invention relates to a radio base station equipment and a mobile station equipment in a mobile communication system that operate as determination stations adapted for a predetermined navigation or associate with other radio base station(s) or mobile station(s) to radio-determine the location of a desired mobile station. The mobile communication system achieves a radio determination economically and reliably while flexibly adapting itself to the substantial traffic distribution and transmission characteristics in individual wireless zones as well as the zone configuration, channel allocation, the procedure of channel control, and the structure of hardware.

Radio base station equipment and mobile station equipment determining location of mobile station by associating with another radio base station or mobile station in a mobile communication system

A searcher for a CDMA receiver apparatus includes a correlator obtaining a correlation value between a spreading code sequence and a spreading code sequence within a received signal, and a non-linear processor carrying out a non-linear conversion to convert one of the correlation value and a predetermined value indicative of the correlation value into correlation value information which has a data width smaller than that of the one of the correlation value and the predetermined value. The correlation value information is used to carry out a search process to search for a synchronizing timing with respect to the spreading code sequence within the received signal.

Searcher for CDMA receiver apparatus

A mobile communication terminal receives a control command transmitted on a down-link from a base station and controls a transmission power so that a reception state on an up-link becomes approximately constant at the base station. The mobile communication terminal is provided with a moving speed inferring unit which infers a moving speed of the mobile communication terminal, and a transmission power controller which varies a varying width of the transmission power depending on the moving speed of the mobile communication terminal.

Mobile communication terminal and transmission power control method therefor

A position acquiring apparatus for specifying the spatial position of a mobile station is provided for a mobile communication system composed of a plurality of base stations fixed on the ground and a mobile station moving on the ground or water or in the air, whereby hand-off control can be executed at proper switching timing or diversity reception control requiring short processing time can be carried out. A receiving unit of the mobile station receives signals transmitted from the base stations, and an extracting unit extracts a predetermined synchronizing signal and an identifying signal contained in each transmitted signal. A time difference detecting unit monitors the timing at which each of the predetermined synchronizing signals is extracted by the extracting unit, to detect a time difference between each extraction timing and predetermined timing. A base station coordinates detecting unit detects position coordinate values of each of the base stations, based on the identifying signals. Based on the time differences and the position coordinate values thus obtained, a mobile station coordinates calculating unit calculates position coordinates of the mobile station.

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Kawasaki, Japan

Kensuke Sawada