Nihon Dempa Kogyo Co., Ltd.

Tobishima Corporation

Kaoru Kobayashi

Kazuo Akaike

Shigeru Takegishi

Nobuo Tsukamoto

Tsukasa Kobata

Naoki Onishi

Tomoya Yorita

Hiroshi Hoshigami

Takashi Nakaoka

Hiroyuki Demura

Hiroshi Chikahisa

Hirotaka Nakahara

Kazunobu Matsumoto

Masayuki Tsutsui

Kouki Kumagai

An angular error detecting device detects an angular error in a receiving direction of a frequency signal from a tracking target with respect to a front direction of an antenna based on a phase difference of a first reception signal received at a first receiving unit of the antenna and a second reception signal received at a second receiving unit having a receiving position in the antenna different from a receiving position of the first receiving unit. The angular error detecting device includes a reception signal output unit, a pilot signal supply unit, a pilot phase difference detection unit, a correction unit, and an angular error detection unit. The angular error detection unit detects the angular error based on the one side corrected at the correction unit and the other side that is not corrected of the sum signal and the difference signal.

Angular error detecting device

An crystal resonator includes a first oscillating circuit that oscillates a crystal resonator at a first frequency, a first impedance adjusting circuit that adjusts an impedance of a first oscillating system including the crystal resonator and the first oscillating circuit, a second oscillating circuit that oscillates the crystal resonator at a second frequency that is different from the first frequency, a second impedance adjusting circuit that adjusts an impedance of a second oscillating system including the crystal resonator and the second oscillating circuit, and a controlling circuit that controls the first impedance adjusting circuit and the second impedance adjusting circuit.

Crystal oscillator and method of manufacturing crystal oscillators

The present invention provides a frequency synthesizer that is switchable at a high speed and includes a few unnecessary frequency components in an output frequency signal. In a frequency synthesizer, a DDSoperates based on a clock signal to generate a reference frequency signal with a predetermined reference frequency, and clock signal supply unitsandswitch the clock signals that have different clock frequencies to supply to the DDS. When the clock signals are switched to operate the DDS, the storage unitstores a combination of a clock frequency f, a reference frequency f, and a dividing number N in association with an output frequency fof the frequency synthesizersuch that a spurious frequency does not exist within a predetermined frequency range and a dividing number of a variable frequency dividerdisposed on a PLL circuitis minimum. Setting unitsandread setting items stored in the storage unitto set respective units.

Frequency synthesizer

An oscillation device corrects a setting value of an output frequency based on a detection result of an ambient temperature of a crystal unit. The oscillation device includes: an oscillation circuit; a temperature detection portion that detects the ambient temperature and outputs a digital value corresponding to the temperature detection value; an accumulator that accumulates the digital value; a rounding processing portion that performs rounding for the digital value accumulated in the accumulator; a digital filter that receives the digital value obtained from the rounding processing portion and obtains a step response gradually increasing from '0' and converging to a step value; and a correction value obtaining portion that obtains a frequency correction value of the oscillation frequency of the oscillation circuit caused by a difference between the ambient temperature and a reference temperature, wherein the setting value of the output frequency is corrected based on the frequency correction value.

Oscillation device

A crystal controlled oscillator of the present disclosure includes: an oscillator circuit for oscillator output, a first oscillator circuit, a second oscillator circuit, a heating unit, a pulse generator, a frequency difference detector, an addition unit, a circuit unit, a frequency measuring unit, a determination unit, and a signal selector. The signal selector is configured to: select a control signal where electric power supplied to the heating unit is smaller than supplied electric power in the detection range in a case where a frequency in a set period at the train of pulses is out of the detection range at the high temperature side; select a control signal where electric power supplied to the heating unit becomes a preset value in a case where a frequency in the set period at the train of pulses is out of the detection range at the low temperature side.

Crystal controlled oscillator and oscillating device

A crystal oscillator includes: an oscillation circuit; first and second oscillation circuits connected to first and second temperature detection crystal units, respectively; a heating portion configured to constantly maintain an ambient temperature; a frequency difference detection portion that obtains, as a temperature detection value, '{(f&#x2212;f)/f}&#x2212;{(f&#x2212;f)/f}', where 'f' and &#x201c;f&#x201d; denote oscillation frequencies of the first and second oscillation circuits, respectively, and &#x201c;f&#x201d; and &#x201c;f&#x201d; denote oscillation frequencies of the first and second oscillation circuits, respectively, at a reference temperature; an accumulator that accumulates the temperature detection value; a rounding processing portion that performs rounding for the temperature detection value accumulated in the accumulator depending on a rounding factor designated independently from the accumulation number; and a heating control portion that controls power supplied to the heating portion based on the temperature detection value subjected to the rounding in the rounding processing portion.

Piece-crystal oscillator and oscillation device

An atmosphere temperature at which a quartz-crystal oscillator and an oscillation circuit are placed is controlled in high accuracy, and an output frequency with high stability is obtained. If oscillation outputs of first and second quartz-crystal oscillators are set to fand f, and oscillation frequencies of the oscillation outputs at a reference temperature are set to fand, respectively, {(f&#x2212;f)/f}&#x2212;{(f&#x2212;f)/f} is calculated by a frequency difference detection unit. A digital value can be obtained by representing this value by 34-bit digital value, corresponding to a temperature. Therefore, this value is treated as a temperature detection value, a difference with a temperature set value is supplied to the loop filter, and the digital value therefrom is converted into a direct-current voltage to control a heater.

Quartz-crystal controlled oscillator

An oscillation device for reducing memory capacity includes a frequency difference detecting unit and a compensation value obtaining unit. When oscillation frequencies of the first and second oscillation circuits are respectively fand f, and oscillation frequencies of the first and second oscillation circuits at a reference temperature are respectively fand f, the frequency difference detecting unit determines a difference corresponding value x corresponding to a difference value between a value corresponding to a difference between fand f, and a value corresponding to a difference between fand f. The compensation value obtaining unit obtains a frequency compensation value of fresulting from ambient temperature different from reference temperature based on the difference corresponding value x, and calculates the frequency compensation value of fby calculating n-order polynomial for X being a value corresponding to x/k, where k is a divide coefficient specific to a device.

A value corresponding to a difference value between a value corresponding to a difference between f1 and f1r and a value corresponding to a difference between f2 and f2r is treated as an instantaneous temperature, where f1 and f2 denote oscillation outputs of the first and second oscillation circuits, respectively, and f1r and f2r denote oscillation frequencies of the first and second oscillation circuits, respectively, at a reference temperature. A first correction value is obtained using an approximation formula of the frequency correction value of f1 based on the value corresponding to the difference value, and a second correction value for canceling a correction residual error is obtained from the correction residual error which is a difference between the first correction value and the frequency correction value actually measured. The frequency correction value is obtained from a sum of the first and second correction values.

Oscillator device with crystal resonators

To perform, in an oscillation device compensating an output frequency based on a detection result of ambient temperature, temperature compensation of the output frequency with high accuracy. First and second quartz-crystal oscillators are structured by using a common quartz-crystal piece, and when oscillation outputs of first and second oscillation circuits respectively connected to these quartz-crystal oscillators are set to f, f, and oscillation frequencies of the first and the second oscillation circuits at a reference temperature are set to f, f, respectively, a frequency difference being a difference between a value corresponding to a difference between fand fand a value corresponding to a difference between fand fis treated as a temperature at that time. Further, based on the frequency difference, a frequency compensation value is determined through polynomial approximation.

Provided is an oscillation device capable of obtaining a stable oscillation frequency by compensating for a change in oscillation frequency caused with an elapse of operating time of a quartz-crystal oscillator. A difference value &#x394;F between a frequency difference between first and second quartz-crystal oscillators after a predetermined period of time has elapsed from a reference time and a frequency difference between the first and second quartz-crystal oscillators at the reference time is determined.

A signal processing unit and a wireless communication device are provided for making it possible to detect a frequency by means of a small scale operation circuit in a short time. The signal processing unit and the wireless communication device are comprised of a carrier data generating unit; a carrier demodulation unit; a matched filter unit that divides carrier demodulated data into a plurality of portions, carries out despread processing and accumulating operation processing as partial correlation processing, further carries out full addition processing for the partial correlation processing result, and outputs correlation detected data; a correlation peak detecting unit that detects a correlation peak from the correlation detected data and outputs correlation peak position information; a coarse frequency deviation detecting unit that outputs a frequency deviation amount with respect to the carrier demodulated data to the carrier data generating unit; and a fine frequency deviation detecting unit that outputs a fine frequency deviation amount from the correlation detected data and the correlation peak position information to the carrier data generating unit.

Signal processing unit and wireless communication device

There is provided a signal processing device and a wireless apparatus capable of not erroneously determining polarity, appropriately performing a spread modulation process, a carrier modulation process, and reception data demodulation process, improving reception accuracy, and miniaturizing a circuit, even when IF carrier frequency shift occurs. The signal processing device and the wireless apparatus includes a spread modulation unit which includes a first differential encoding process section for performing a differential encoding process on a reception data, a differential encoding process section for performing a second differential encoding process on the output, and a spread modulation process section for performing a spread modulation process on the output using a spread code; a carrier modulation unit which quadrature-modulates a transmission data spread modulation signal and a continuous wave; and a reception data decoding unit which performs a correlation process twice and a delay detection process twice.

Signal processing device and wireless apparatus

A signal processing unit and a wireless communication device are comprised of a carrier data generating unit; a carrier demodulation unit; a matched filter unit that outputs correlation peak detected data; a correlation peak detecting unit that detects a correlation peak from the correlation detected data and outputs correlation peak position information; a coarse frequency deviation detecting unit that detects a frequency component in accordance with a carrier frequency deviation amount with respect to carrier demodulated data and outputs a frequency deviation amount to the carrier data generating unit; a fine frequency deviation detecting unit that outputs a fine frequency deviation amount to reduce the frequency deviation amount from the correlation detected data and the correlation peak position information to the carrier data generating unit; and a control unit that inputs the correlation peak position information and adjusts a processing clock signal.

Provided is a matched filter whose circuit scale can be made significantly smaller by reducing the number of multipliers for a despreading process and the number of adders for an accumulating process. For each in-phase/orthogonal component, the matched filter includes a dual-port RAM that separates written samples into 128 groups each of 32 samples which are collectively read out group by group in order at a speed faster than a write speed in write mode, a bit separating section that separates data read group by group into 32 samples and simultaneously outputs the 32 samples, and 32 despreading/accumulating circuits that, with 16 samples sequentially input from 16 groups being taken as one block, sequentially despread individual samples, accumulate despreading results, and output accumulated values for each block. The matched filter further includes an accumulating section that accumulates absolute values for each block from in-phase/orthogonal outputs of the despreading/accumulating circuits, and outputs correlation value data.

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Saitama, Japan

Kaoru Kobayashi