Nippon Telegraph and Telephone Corporation

Japan Aerospace Exploration Agency

Seiji Yoshida

Takashi Hirose

Keisuke Nishi

Takeshi Yamamoto

Akihiro Morita

Youichi Fukada

Kazuo Shimodaira

Yoji Kurosawa

Jun Terada

Naotaka Shibata

Jun-ichi Kani

Shigeru Kuwano

Kazuaki Matsuura

Masakatsu Fujiwara

A signal receiving equipment includes a receiver configured to receive signals from a GNSS satellite, a memory, and a processor configured to select a plurality of signals from among the signals received by the receiver using a preset first parameter; perform at least positioning of a location by code-based positioning using the plurality of signals selected using the first parameter; select a plurality of signals from among the signals received by the receiver using a preset second parameter; and perform positioning of a location and time synchronization by carrier-phase-based positioning using the plurality of signals selected using the second parameter, with coordinates indicated by the location positioned by the code-based positioning as initial coordinates.

Signal receiving equipment, signal processing method and program

A position measurement system includes one or more computers each including a memory and a processor configured to measure an absolute position of a mobile object, attach a first time stamp to an absolute position measurement result, and output the absolute position measurement result with the first time stamp; measure a relative displacement of the mobile object, attach a second time stamp to a relative displacement measurement result, and output the relative displacement measurement result with the second time stamp; and execute positioning computation for calculating the absolute position of the mobile object based on the absolute position measurement result with the first time stamp and the relative displacement measurement result with the second time stamp, attach a third time stamp to a positioning computation result, and output the positioning computation result with the third time stamp.

Position measurement system, positioning calculation apparatus, position measurement method and program

A position measurement apparatus for measuring an absolute position of a mobile object, the position measurement apparatus includes one or more computers each including a memory and a processor configured to measure the absolute position of the mobile object based on signals transmitted from navigation satellites; measure a displacement of the mobile object from a certain position; and switching between measuring the absolute position of the mobile object and measuring the displacement of the mobile object from the certain position in accordance with a plan which is created in advance or created during movement of the mobile object.

Position measurement apparatus, position measurement method and program

A navigation satellite system reception apparatus can eliminate multipath signals without direct waves of invisible satellites and can implement time synchronization. A satellite orbit information acquisition unit acquires orbit information of a satellite, an installation position information acquisition unit acquires position information of an installation position, an azimuth meter acquires azimuth information of an azimuth in which a wall surface of a nearby obstruction extends, and an azimuth mask generation unit calculates a mask region for selecting a satellite to be a target of processing based on the azimuth information. A positioning and time synchronization processing unit calculates an azimuth and an angle of elevation of each satellite, selects a satellite to be a target of processing bas, and performs the positioning processing or the time synchronization processing based on a satellite signal received from the selected satellite.

Navigation Satellite System reception device, method for processing Navigation Satellite signal from same, and program

A positioning system includes equipment that receives a signal from a GNSS satellite, and a server apparatus that is connected to the equipment via a communication network. The equipment includes a memory and a processor configured to transmit information indicated by the signal to the server apparatus, and perform positioning of the equipment by using the information indicated by the signal. The server apparatus includes a memory and a processor configured to perform positioning of the equipment by using the information indicated by the signal received from the equipment.

Positioning system, equipment, server apparatus, positioning method and program

A navigation satellite system reception apparatus includes a navigation satellite signal reception unit that calculates a first reception position, and a control unit that calculates an initial value of the first reception position and an orbit position of each of four or more navigation satellites, calculates, based on the calculated first reception position, the calculated orbit position, and time information from the first navigation satellite signals, arrival time of each of the first navigation satellite signals, extracts, based on the calculated arrival time, a second navigation satellite signal, calculates, based on the extracted second navigation satellite signal, a second reception position, recursively performs, by using the calculated second reception position, a calculation process of the arrival time and an extraction process of the second navigation satellite signal, and performs, based on a second navigation satellite signal extracted at end of recursive processing, the positioning process or the time synchronization process.

Navigation satellite system reception device, method for processing navigation satellite signal from same, and program

A time synchronization method that is capable of selecting whether synchronization, by a timepiece unit that generates a time signal synchronized with a standard time and outputs it to an exterior, with the time is performed by time information obtained by receiving a radio wave including information relating to the time, or is performed by means of a holdover performed using a clock signal from an internal or external clock source. A schedule having a first time period in which the above-mentioned time information is used, and a second time period by means of the holdover is determined according to temporal reception characteristics of the radio wave at a reception location of the radio wave, and according to the schedule, supplying the timepiece unit with the time information or supplying the timepiece unit with the clock signal from the internal or external clock source.

Time synchronization device, and method and program therefor

A satellite signal reception characteristic estimation apparatus includes a satellite orbital information collection unit that collects and outputs orbital information for a satellite; a peripheral environment spatial information collection unit that collects spatial information for a peripheral environment of an installation position of a satellite antenna; a positional information collection unit that collects and outputs positional information for the installation position of the satellite antenna; and a simulation server unit that estimates reception characteristics of satellite signals at the installation position of the satellite antenna by performing a simulation based on the orbital information, the spatial information, and the positional information outputted from the satellite orbital information collection unit, the peripheral environment spatial information collection unit, and the positional information collection unit.

Satellite signal reception characteristic estimation apparatus, method thereof, and program thereof

A navigation satellite signal reception apparatus includes a satellite antenna; a satellite orbital information collection unit that collects orbital information of a navigation satellite; a peripheral environment spatial information collection unit that collects spatial information for a peripheral environment of an installation position of the satellite antenna; a positional information collection unit that collects positional information for the installation position of the satellite antenna; and a signal correction unit that performs a determination process to determine whether a navigation satellite associated with the received satellite signal is in a directly viewable state or in a non-directly-viewable state from the installation position of the satellite antenna, and that performs a correction process on a satellite signal from a navigation satellite in an NLOS state, on the assumption that the satellite signal is a reflected wave.

Satellite signal reception apparatus, satellite signal reception method and program therefor

Since a sampling frequency of RRU is always constant, A/D conversion may be performed with a sampling frequency higher than necessary with respect to a frequency band width of a radio signal. A sampling frequency change function, and the sampling frequency is reduced in a range where a aliasing component does not deteriorate signal quality of a desired signal component when the sampling frequency is decreased, based on radio band allocation information, or signal transmission between BBU and RRU is stopped in a no signal section, whereby a band required for digital RoF transmission between the BBU and the RRU is reduced.

Distributed radio communication base station system, base band unit, remote radio unit, and method for operating distributed radio communication base station system

The object of the invention is to provide a lightweight mechanism that changes the distribution of a flow rate of air for combustion supplied into each burner, without providing a mechanical movable part in a passage for high-temperature and high-pressure air for combustion in a combustor having a plurality of burners such as a pilot burner and a main burner. The combustor equipped with an air flow rate distribution control mechanism based on a fluidic element in accordance with the present invention has a plurality of burners such as a main burner and a pilot burner, wherein with the fluidic element being disposed upstream of a passage of air for combustion that is supplied to each burner, and means for sucking out or blowing out air into a control air passage of the fluidic element being provided, the distribution of a flow rate of the air flowing into the burners is controlled by changing a flow direction of the air for combustion.

Combustor equipped with air flow rate distribution control mechanism using fluidic element

A main swirler of a triple annular configuration that is partitioned by a pre-filmer and a separator is installed in an inlet port of a main air flow channel. The vicinity of the inner wall of the main air flow channel provided with a main fuel injection port is bulged radially outward from the innermost surface (innermost surface of a small swirler) of a main swirler. Further, a distance from the main fuel injection port and the pre-filmer is set such that an effective opening area between the pre-filmer and 'the inner wall of the main air flow channel provided with the main fuel injection port' is equal to an effective opening area of the small swirler. The swirling directions of the swirlers of the main swirler are 'clockwise'-&#x201c;counter-clockwise&#x201d;-&#x201c;clockwise&#x201d; respectively along the radial outward direction when the swirling direction of the innermost swirler is taken as &#x201c;clockwise&#x201d;.

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Tokyo, Japan

Seiji Yoshida