Abstract: A parameter of an adaptive filter is optimized so that inter-symbol interference having an amount corresponding to an inserted fixed filter remains.

Abstract: A relief valve includes a valving element, a movable holder, a housing having a guide hole and a valve seat, and a resilient member. The valving element is lifted from its seated state, in which the valving element is engaged with the valve seat, toward a pressurizing chamber in a lift period. The lift period includes a lift first period and a lift second period. An amount of the lift of the valving element reaches a set distance in the lift first period. The lift second period is after the amount of the lift of the valving element has reached the set distance. The movable holder slides inside the guide hole both in the lift first period and in the lift second period. A minimum clearance area between the movable holder and the guide hole is larger in the lift second period than in the lift first period.

Abstract: An optical digital transmission system of the present invention newly defines one second negative stuff byte in an overhead area for accommodation of the client signals with multiplexing into the OTU frame, newly defines one third positive stuff byte in a corresponding tributary slot in a payload area for accommodation of client signals with multiplexing, newly defines stuff control bits that is used for decision of the use of the second negative stuff byte and the third positive stuff byte in three different places in the overhead area for client signal accommodation with multiplexing, performs control by using the newly defined stuff control bits when accommodation of the client signal with the third positive stuff byte or the second negative stuff byte is required, and performs stuff control without using the newly defined stuff control bits when accommodation of the client signal by the third positive stuff byte and the second negative stuff byte is not required.

Abstract: A digital transmission system includes at least a client device and a transmission device, and rate-adjusts the client signal transmitted from the client device to the transmission device before accommodating/multiplexing the signal in a frame. The transmission device includes a rate adjusting unit and a frame processing unit. The rate adjusting unit encapsulates the client signal by using a predetermined frame structure, inserts an idle pattern if necessary, and performs rate adjustment into the bit rate which can be contained in the frame. The frame processing unit accommodates/multiplexes the signal after the rate adjustment. The digital transmission system inserts a bit string of the client signal directly in a payload area of the digital frame, or accommodates and multiplexes it. Alternatively, a specific pattern is accommodated in the payload area, or accommodated and multiplexed after performing a reversible digital signal processing.

Abstract: A receiver device receives a signal inputted to one or a plurality of ports as a plurality of received signals, and includes: a phase offset estimating unit that, on the basis of a unique word of each signal block contained in said received signal, estimates the phase offset, and a phase offset compensating unit that, on the basis of a phase offset estimated by said phase offset estimating unit, compensates the phase offset; the receiver device uses a known signal component (unique word) contained in a frequency-domain equalized signal to compensate the phase offset, whereby it compensates complex phase offset fluctuation, and estimates the phase offset of a signal obtained at each port.

Abstract: A stem is installed to an injector body and is resiliently deformable upon receiving a pressure of high pressure fuel conducted through a high pressure passage of the injector body. A strain gauge is installed to the stem to sense a strain generated in the stem. A molded IC device executes an amplifying operation, which amplifies a signal received from the strain gauge. The stem, the strain gauge and the molded IC device are integrally assembled together to form a fuel pressure sensing unit, which is installed to the injector body by threadably fastening a threaded portion, which is formed at the stem, to the injector body.

Abstract: A fuel injection apparatus includes a body, a nozzle, a pressure control unit, a physical quantity measurement unit, a first terminal, a second terminal, a positioning member, and a resin connector main body portion. The pressure control unit controls opening and closing of the nozzle The physical quantity measurement unit outputs an electric signal in accordance with a physical quantity of high pressure fuel. The first terminal is connected to the pressure control unit. The second terminal connected to the physical quantity measurement unit. The positioning member integrally holds the first terminal and the second terminal and locates the first terminal and the second terminal at predetermined positions. The connector main body portion receives therein the positioning member.

Abstract: An optical modulator and an optical transmission system convert continuous light of a multiple wavelength light source, which generates the continuous light with a fixed and complete phase but different frequencies, to a modulator driving signal so as to generate a light subcarrier with each frequency at the center and modulate the continuous light to the light subcarrier by using the modulator driving signal. In the case where an optical modulation is carried out by an optical IQ-modulator, transmitting data, for example, is converted to two parallel data A(t) and B(t), an I phase signal, in which the data A(t)+B(t) are modulated with a clock signal with a frequency ?, and a Q phase signal, in which the data A(t)?B(t) are modulated with a clock signal with a ?/2 phase shifted, are generated, and the I phase signal and the Q phase signal are applied to electrodes of the optical IQ-modulator, respectively.

Abstract: In a fuel injector, a body has formed therein a spray hole and a fuel supply passage. Fuel supplied to the fuel supply passage is delivered to the spray hole. A fuel pressure sensor produces a signal indicative of a pressure of the fuel. First terminals are attached to the fuel pressure sensor, and include a terminal for outputting the signal. The fuel pressure sensor is threadedly installed in the body while the plurality of first terminals are rotated about a preset axis. A connector includes a housing attached to the body, and second terminals supported by the housing for external electric connection of the fuel pressure sensor. Electrodes are each arranged to extend around the preset axis in a circular arc. Each of the electrodes electrically connects a corresponding one of the first terminals to a corresponding one of the second terminals.

Abstract: Provided is a frequency offset estimation apparatus that appropriately estimates and compensates for a frequency offset of a received signal when estimating the frequency offset which is the difference between a carrier frequency of the received signal and the frequency of an output signal of a local oscillator.

Abstract: When a circuit that calculates a frequency offset using a shape of a frequency spectrum is implemented by hardware, the circuit size can be reduced.

Abstract: A high-performance optical OFDM receiver is realized. A subcarrier separation circuit receives an optical OFDM signal consisting of two subcarriers A and B and separates a subcarrier component, signal light and first local oscillator light are input to the subcarrier separation circuit, the subcarrier separation circuit converts the signal light and the first local oscillator into a baseband electrical signal, the subcarrier separation circuit converts the baseband electrical signal into a digital signal, the subcarrier separation circuit shifts the frequency of the converted digital signal so that a center frequency of the subcarrier A becomes zero, and the subcarrier separation circuit adds a frequency shifted signal to a signal obtained by delaying the frequency shifted signal by ½ of a symbol time to separate a component of the subcarrier A.

Abstract: A polarization state of a transmission signal can be changed at a high speed based on a symbol-rate By switching a first switch, a second switch, and a third switch with time, one of an X-polarized wave_I-signal as a Y-polarized wave_I-signal, a signal caused by performing logical inversion for an X-polarized wave_I-signal, an X-polarized wave_Q-signal and a signal caused by logical inversion for an X-polarized wave_Q-signal is input to a second modulator. Further, by switching the first switch, the second switch and the third switch with time, the second modulator is input one of the X-polarized wave_I-signal as the Y-polarized wave_Q-signal, the X-polarized wave_I-signal, the signal caused by performing logical inversion for the X-polarized wave_I-signal, the X-polarized wave_Q-signal and the signal caused by performing logical inversion for the X-polarized wave_Q-signal. Thereby, a polarization state of a transmission signal can be changed at high speed based on a symbol-rate speed.

Abstract: A device and method for adjusting the chromatic dispersion in an optical transmission system includes an optical element having a temperature-dependent chromatic dispersion. The device and method further include a device for adjusting a temperature or a temperature distribution of at least one region of the optical element for providing a predefined chromatic dispersion of the optical element. Therefore, the chromatic dispersion of the optical element may be regulated along an optical transmission path.

Abstract: A photoelectric switch can be widely applied with a function to sensuously and intuitively display a light-receiving amount as an artificial numeric value in a given range. A preset display value “100” is set to an average value of sampled light-receiving amounts (S2). A preset display value “0” is allocated to a light-receiving amount of “0” already held by the photoelectric switch (S3), to obtain a preset display conversion factor (S4). When an operation based on this preset display conversion formula is disadvantageous, an average value of the sampled actual light-receiving amounts is set to a preset display value “0 (zero)” (S23), and a preset display conversion formula, obtained by substituting the above actual light-receiving amount for the light-receiving amount with respect to the preset display value “0” in the already created preset display conversion formula, is created (S22).

Abstract: A frequency domain multiplexed signal receiving method which decodes received signals that are multiplexed in a frequency domain, includes: a digital signal acquisition step of acquiring digital signals from the received signals that are multiplexed in the frequency domain; an offset discrete Fourier transform step of applying an offset discrete Fourier transform to odd discrete point numbers based on the acquired digital signals; and a decode step of decoding frequency domain digital signals in the frequency domain obtained by the offset discrete Fourier transform, and that are the frequency domain digital signals of one or more frequency channels.

Abstract: In order to compensate for chromatic dispersion caused by optical fiber transmission in a communication system with coherent detection using optical signals, specific frequency band signals are used to enable estimation of a chromatic dispersion value.

Abstract: To enable signal position detection, frequency offset compensation, clock offset compensation, and chromatic dispersion amount estimation in a communication system based on coherent detection using an optical signal, even on a signal having a great offset in an arrival time depending on a frequency due to chromatic dispersion. An optical signal transmitting apparatus generates specific frequency band signals having power concentrated on two or more specific frequencies and transmits a signal including the specific frequency band signals. An optical signal receiving apparatus converts a received signal into a digital signal, detects positions of the specific frequency band signals from the converted digital signal, estimates frequency positions of the detected specific frequency band signals, and detects a frequency offset between an optical signal receiving apparatus and an optical signal transmitting apparatus.

Abstract: An optical transmission system for performing frequency synchronization even with a client signal with low frequency accuracy, and for transmitting thereof by accommodating/multiplexing without causing a bit slip. A new overhead is added to the entire client signal, and the signal including the new overhead being stuffed is transmitted in conjunction with a plurality of stuffing bits as an optical signal wherein a data storing bit for a negative stuffing, a stuffing information notification bit, and a stuff bits inserting bit for a positive stuffing in the payload are defined in plurality as stuffing bits for adjusting clock frequencies of the client signal in this new overhead.

Abstract: An optical digital transmission system of the present invention newly defines one second negative stuff byte in an overhead area for accommodation of the client signals with multiplexing into the OTU frame, newly defines one third positive stuff byte in a corresponding tributary slot in a payload area for accommodation of client signals with multiplexing, newly defines stuff control bits that is used for decision of the use of the second negative stuff byte and the third positive stuff byte in three different places in the overhead area for client signal accommodation with multiplexing, performs control by using the newly defined stuff control bits when accommodation of the client signal with the third positive stuff byte or the second negative stuff byte is required, and performs stuff control without using the newly defined stuff control bits when accommodation of the client signal by the third positive stuff byte and the second negative stuff byte is not required.