摘要:
To provide a positioning system, a positioning method, and a positioning server, which are capable of improving accuracy in detection of a position. In a positioning system, three or more access points connected to a terminal station by wireless communication are connected to a positioning server through a network, the access points transmit, to the positioning server, information regarding times of having received a signal transmitted from any one of the access points or the terminal station, and the positioning server measures a position of the terminal station based on the information regarding the times, the information having been received from the access points. In the positioning system, the access points select a communication method for maximizing a strength of the signal received from the terminal station and receive the signal from the terminal station, and the positioning server measures the position of the terminal station based on the information regarding the times, the information having been received from the access points.
摘要:
The present invention reduces the number of base stations required to carry out terminal position detection. A base station which serves for terminal position detection using radio signals comprises an antenna to transmit and receive a radio signal; a radio signal receiver which generates a received signal from the radio signal received; a signal processing unit which processes the received signal and generates a transmit signal; a radio signal transmitter which generates a radio signal from the transmit signal; a control unit which exerts control of the base station operation; and a signal processing unit for position detection which performs signal processing for terminal position detection. A signal receivable range with which a signal can be received by the radio signal receiver is made longer than a signal transmission range with which a signal is transmitted by the radio signal transmitter.
摘要:
When a strobe flash is not emitting light, a photoreception current that is output from a phototransistor is detected and correction current corresponding to amount of extraneous light is produced by a voltage-controlled current source. Further, a light-emission control apparatus, receives emitted light reflected from the subject and halts the light emission when a value obtained by integrating a photoreception signal exceeds a first predetermined threshold value. If a period of time from start of light emission by the discharge tube to that at which the integrated value exceeds the threshold value falls within a predetermined period of time, the integrated value is reset and integration is performed again. Further, the aperture of a diaphragm is reduced and the threshold value is raised from the first threshold value to a second threshold value.
摘要:
A code division multiple access (CDMA) mobile communication system with improvements to permit stable reception with a minimum of bit error. The system comprises a voltage-controlled oscillator for supplying a carrier to a radio frequency quadrature demodulator, and a frequency controller for detecting a frequency error from a phase correction signal of the first step to generate a control signal that controls the oscillator. The frequency controller includes an extracting circuit and an integrating circuit. The extracting circuit extracts a phase change based on the frequency error derived from the phase correction signal of the first step and from a signal preceding that signal by a predetermined delay time. The integrating circuit integrates the phase change and outputs the integrated result as the control signal. The predetermined delay time is preferably set within a range not exceeding the delay time needed for averaging by an averaging circuit that receives the phase correction signal of the first step and outputs a phase correction signal. The carrier to a radio frequency quadrature modulator is preferably supplied from the voltage-controlled oscillator.
摘要:
A power-source system includes: a power source; a voltage monitoring unit for monitoring a voltage of the power source to detect that the voltage falls below a consumption-limit level below which the use of the power source is to be limited; a consumption limiting unit for limiting the use of the power source when the voltage falls below the consumption-limit level; and a consumption-limit prohibiting unit for prohibiting the consumption limiting unit from limiting the use of the power source when the voltage of the power source falls below the consumption-limit level because of a momentary voltage fall different from a voltage fall corresponding to a discharge curve of the power source.
摘要:
A code division multiple access (CDMA) mobile communication system with improvements to permit stable reception with a minimum of bit error. The system comprises a voltage-controlled oscillator for supplying a carrier to a radio frequency quadrature demodulator, and a frequency controller for detecting a frequency error from a phase correction signal of the first step to generate a control signal that controls the oscillator. The frequency controller includes an extracting circuit and an integrating circuit. The extracting circuit extracts a phase change based on the frequency error derived from the phase correction signal of the first step and from a signal preceding that signal by a predetermined delay time. The integrating circuit integrates the phase change and outputs the integrated result as the control signal. The predetermined delay time is preferably set within a range not exceeding the delay time needed for averaging by an averaging circuit that receives the phase correction signal of the first step and outputs a phase correction signal. The carrier to a radio frequency quadrature modulator is preferably supplied from the voltage-controlled oscillator.
摘要:
The present invention relates to a sheet feeding apparatus comprising a sheet supporting means for supporting sheets, a feeding means for feeding the sheets on the sheet supporting means in a sheet feeding direction, a separating means for rotating in a direction opposite to the sheet feeding direction to separate the sheets sheet by sheet in pressurized contact with the feeding means and a transmitting means for transmitting drive force of the feeding means to the separating means. A circumferential speed of the separating means is set smaller than a circumferential speed of the feeding means.
摘要:
The document information management system according to the present invention comprises data base with a plurality of document files previously stored therein, a medium form having a document information section with document information recorded thereon and a bar code information section with electronic information corresponding to contents of the document information converted to bar code information and stored therein, a marking unit for giving a selection mark by selecting a desired word from a medium form, a reading unit for reading a selection mark and bar code information from a medium form with the selection mark given thereto, a retrieving unit for retrieving a corresponding document file from a data base using a word with a selection mark given thereto as a key word according to the selection mark and bar code information, and an output unit for outputting the retrieved document file as related information.
摘要:
In a spread spectrum communication system, one (Wn) of a series of orthogonal codes for spectrum spreading is assigned to signal-to-noise ratio measurement in a terminal. On the basis of a noise signal detected by de-spreading a signal received from an antenna with the above described orthogonal code Wn and a pilot signal, each terminal derives a signal-to-noise ratio. Each terminal transmits the signal-to-noise ratio to the base station as a power control signal. On the basis of signal-to-noise information received from each terminal as the power control signal, the base station controls signal transmission power for each terminal.
摘要:
A coordinate input device includes a writing panel which includes a writing surface having two vertical sides and two horizontal sides. A plurality of transmitting units transmit surface acoustic waves SAW to propagate the SAW within the writing panel in one of a vertical direction and a horizontal direction through reflection. A plurality of receiving units receive the SAW from the plurality of transmitting units through reflection, and output detection signals in response to the received SAW, so that coordinates of a specified point on the writing panel are detected based on the detection signals. A plurality of reflectors, provided on the four sides of the writing surface, reflect the SAW from the transmitting units inwardly to the writing panel and reflect the reflected SAW to the receiving units. In the coordinate input device, the plurality of reflectors, the plurality of transmitting units, and the plurality of receiving units are divided into at least two groups with respect to one of the vertical direction and the horizontal direction, respectively, and symmetrically placed about a predetermined line of the writing panel.