Hitachi, Ltd.

Hitachti, Ltd.

Atsushi Ogino

Hideya Suzuki

Ryota Yamasaki

Tomoaki Ishifuji

Takaki Uta

Mikio Kuwahara

Takashi Yano

Nobukazu Doi

Kenzaburo Fujishima

Katsuhiko Tsunehara

Masaaki Shida

Hiroshi Shimizu

Masahiko Saito

Kumiko Takikawa

Tsuyoshi Tamaki

Kenichi Mizugaki

Jun Maeoka

Shinichi Obata

Nobuaki Kohinata

Koji Watanabe

Takeshi Kato

Naoto Matsuzawa

Katsuhiko c/o Hitachi Ltd Intellectual Property Group Tsunehara

Takahashi c/o Hitachi Ltd Intellectual Property Group Yano

Hideya c/o Hitachi Ltd Intellectual Property Group Suzuki

Ryota c/o Hitachi Ltd Intellectual Property Group Yamasaki

Masaaki c/o Hitachi Ltd Intellectual Property Group Shida

Nobukazu Hitachi Kokusai Electric Inc Doi

In a measurement system that comprises plural measurement devices classified by groups, and plural data processing devices on a network that receives and processes measured data from the measurement devices, the data processing devices are smoothly allocated. The measurement devices belong to groups based on the areas in which they are located, and respectively transmit measured data to a multicast address defined for each of the groups to which they belong. A management device detects an overloaded or failed data processing device, stops data processing on a multicast address at which the data processing device receives data, alternatively commands another less loaded data processing device to join the multicast group, receive measured data transmitted to the multicast address, and process the data.

Measurement system, management device and processing distribution method using the system

In a position detection system utilizing a WLAN supporting multiple data transfer rates, it is possible to reduce the number of required installed base stations, so system construction costs can be lowered. In a wireless station, a transmitted signal is judged at the time of transmission, and in case it is normal user data, the signal is transmitted by setting optimal transmission parameters for which a high communication throughput with wireless communication is obtained, and in case it is a position detection signal, the aforementioned signal is transmitted by setting transmission parameters for which the service range is increased. As a transmission parameter for which the service range is increased, a low data transfer rate or a long preamble length is used.

Method, system and apparatus for detecting a position of a terminal in a network

In any indoor location, whenever operating a wireless terminal position detecting system comprising a transferable wireless terminal, a plurality of base stations individually allowing a connection from said wireless terminal, and a plurality of wireless receiving stations individually receiving wireless signal from said terminal and base stations, there is a problem in terms of the provision of a method for minimizing positional detection error on the part of said wireless terminal and a method for practically realizing said method. Hence, to solve the above problem, the present invention provides a wireless terminal position detecting method featuring the function to evaluate the result of measurement against wireless signals from an objective wireless terminal received by individual wireless receiving stations based on a definition of a plurality of position detectable areas designating a geographic range required for detecting actual position of said objective wireless terminal and also based on another definition for specifying plural wireless receiving stations each being located at a predetermined known position allocated for individual areas for detecting actual position of the objective wireless terminal in respective position detectable areas before eventually determining the actual position of the objective wireless terminal.

Wireless terminal position detecting method and system therefor

At least three base stations transmit a specific signal pattern at given intervals. This allows a mobile station that received this signal pattern to locate itself by using the positional information about the base stations, sending timing (or information on phase shift from the reference time) of each signal pattern from the base stations, and signal pattern receiving time information. At least one of the above base stations changes the sending timing of the signal pattern. On this occasion, the mobile terminal or station is notified of the altered reference time offset (or information on phase shift from the reference time) of the sending timing or updated sending timing of the signal pattern.

Method of providing location service using CDMA-based cellular phone system, a method of measuring location and location system

When one base station to which a terminal is to connect is determined from a plurality of base stations in a wireless communication system, the best base station is selected according to the communication quality or the content of communication services. In the wireless communication system, the plurality of base stations are classified into a plurality of groups. Indexes of communication quality between the base stations and the terminal are obtained and, for each group, the characterizing quantities of the indexes of communication quality are calculated. The base station group with which the terminal is to communicate is specified based on the characterizing quantities. One of the base stations in the specified group is determined as a communication destination base station.

Method for selecting base station

A method, system, and apparatus are provided for detecting a position of a terminal in a network accurately without a GPS receiver. In one example, a method for locating a position of a terminal includes calculating a position of a base station; detecting a clock time difference between the base station and another base station; measuring a reception timing of a signal received by the base station from the terminal; and locating the position of the terminal using at least the position of the base station, the clock time difference, and the reception timing.

Method, system, and apparatus for detecting a position of a terminal in a network

In a position detection system for detecting a position of a terminal apparatus of a radio communications system, a position detection time is shortened using a position detection method for determining signal times-of-arrival between the terminal apparatus and base stations neighboring the terminal apparatus. According to the present invention, means for generating a database in which received power information about signals transferred between the terminal apparatus and the base stations neighboring the terminal apparatus corresponds to position information about the terminal apparatus, and for determining the position information by searching received power information obtained in the position detection from the database, and means for determining the position by use of signal times-of-arrival are executed in parallel. Then, the use of a result of the means which has detected the position earlier than another means shortens the position detection time.

System and method for position detection of a terminal in a network

A position calculation method includes a step of calculating error degradation quantities about respective measurement results ('distance-ranging results') on distances between respective reference stations and a detection-target station from the respective distance-ranging results and positions of the respective reference stations, a step of calculating weight-assigning factors about the respective distance-ranging results based on the respective error degradation quantities, a step of checking the number of valid distance-ranging results, and a step of calculating the position of the detection-target station based on the respective distance-ranging results, the positions of the respective reference stations, and the respective weight-assigning factors.

Position calculation method and storage medium storing a program therefor

A method and system for detecting the position of a mobile unit efficiently and with high precision in a multipath environment. A wireless position detection system made up of a mobile station containing a wireless communication means to allow sending and receiving multiple to and from mutually different antenna positions and, a base station for performing wireless communication with mobile stations containing a wireless communication means and, multiple wireless receivers for receiving each of the multiple signals sent by the wireless communication means between the base stations and, a server for detecting the position of the mobile station from each wireless receiver and from the position of the base station, and the time relating to received signals measured by the multiple wireless receivers.

Wireless position measurement method and wireless position measurement system

To efficiently obtain and register the position of a base station in a database. A map or a drawing, such as a plan of a building, is read and displayed on display unit (). Then, on the basis of the real coordinates of a first reference position Pon the display unit and a real distance per a unit of display, the real coordinates of a second reference position Pset on the display unit () are obtained. Then, on the basis of the real coordinates of the second reference position and an offset from the second reference position to the base station (), the real coordinates indicating the position Pwhere the base station is located are obtained, and these real coordinates indicating the position Pare registered in the database.

Wireless base station position setting method, wireless communication system, and program

In a positioning system using the time difference of arrival of signals between a station and a plurality of access points, each of the access points repeatedly measures a signal for calculating a position from the station, while changing any of time, the position of the station, and a frequency in use, and accumulates a plurality of measurement data. A position calculation server determines a given timing on each of a plurality of delay profiles created based on the measurement data obtained from the access points as a reception timing sample for the signal, performs a combination process with respect to the plurality of reception timing samples, and determines one reception timing for each of the access points. The position calculation server calculates the time difference of arrival of signals between the station and the access points based on the reception timings and calculates the coordinates of the position of the station.

Positioning system and method based on time difference of arrival

In calculation of a position of a terminal, there arises, when creating a delay profile, a problem to select a transmission code for a sector of a base station to create the delay profile. According to a position of a base station and a bearing of each antenna forming a sector of the base station, a wireless position calculation method selects a transmission code for a sector of a base station to create a delay profile. Under a condition that the number of delay profiles to be created is limited, each delay profile is created in consideration of the antenna bearing. Therefore, the number of base stations at mutually different positions is increased to calculate the position and precision of the position calculation is improved.

Position calculation method and a mobile terminal and a server therefor

There are provided a cellular telephone device and transmitter for setting a cellular telephone to answering mode and a telephone section to sleep status when communication forbidding information is received, and restoring telephone section operation when there is no communication forbidding information and canceling silent mode and answering mode; and automatically setting silent mode and answering mode when a communication forbidding signal is received, and maintaining the telephone section operation status when there is no communication forbidding information, and canceling silent mode and answering mode.

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Kodaira, Japan

Atsushi Ogino