Seiko Epson Corporation

Michio Kobayashi

Satoshi Nebashi

Tatsuya Shimoda

Norimitsu Baba

Tsukasa Kosuda

Masaki Hoshina

Hiroshi Hirayama

Yoshihiro Okamoto

Hisashi Osawa

Tetsuya Matsui

A characteristic automatic compensating apparatus of an oscillator includes oscillating means, temperature detecting means, characteristic determining means for measuring a drift value of an oscillating frequency while changing the temperature and for determining a coefficient of an approximated equation representing temperature and the drift value, storing means for storing the coefficient, drift value predicting means, and characteristic updating means for updating the coefficient by the measured drift value of the oscillating frequency and the temperature, wherein the characteristic determining means represents the approximated equation representing the characteristic of the temperature detected by the temperature detecting means and the drift value of the oscillating frequency of the oscillating means by a polynomial.

Characteristic automatic compensating apparatus, characteristic automatic compensating method, characteristic automatic compensating program of oscillator and positioning signal receiver

The present invention provides an information authenticating apparatus and an authenticating station adapted to improve the probative value of data as evidence by ensuring a high objectivity of the data. The information authenticating apparatus comprises a digital camera and an authenticating information adding section which adds authenticating information to digital data entered by the digital camera. The authenticating station comprises, on the other hand, a communication unit which receives the digital data from the information authenticating apparatus, and a digital signature affixing section. The digital signature affixing section affixes the digital signature to the digital data received by the communication unit when authenticating that the digital data have been entered by the digital camera.

Information authenticating apparatus and authenticating station

A device and method are provided to reduce the time required for positioning by a GPS without allowing specific parties to occupy a communication channel. An initial location acquisition unit specifies a location of a broadcasting station based on a terrestrial digital broadcasting from the broadcasting station to set the location of the broadcasting station as an initial location for positioning in a positioning unit, and the positioning unit determines a present location by receiving a radio wave from a GPS satellite.

Positioning device, mobile terminal, positioning method, and positioning program

Method, apparatus, system and information storage medium for wireless

A pulsimeter analyzes a pulse wave signal output by a pulse wave sensor worn on a part of the body while exercising, enables extraction of only the pulse wave component without being affected by movement of the body, and evaluates a detection state indicative of whether the pulse wave sensor is detecting the pulse. A pulse wave component extractor extracts a pulse wave component from the result of a time-frequency analysis of a pulse wave signal. A pulse rate calculator calculates the pulse rate per minute based on the pulse wave component extracted by the pulse wave component extractor. The pulse rate is then displayed. A detection state of the pulse wave sensor is also displayed by providing a detection state evaluator for determining the presence of a pulse wave component based on the result output by the pulse wave component extractor.

Pulsimeter

A magneto-optical recording and reproducing apparatus achieving an improvement in high density recording and bit error correction rate. The magneto-optical recording and reproducing apparatus comprises coding and modulating means for (1,7) RLL encoding and then NRZI encoding a digital information series {A.sub.i }; recording and reproducing means for recording the encoded series {a.sub.i } to a magneto-optical recording medium, and reproducing an analog signal from the medium as elementary waveform sequence e(t) using an optical head; a transversal filter type waveform equalizer for waveform equalizing elementary waveform sequence e(t) by applying the transfer function (1+2D+2D.sup.2 +D.sup.3) of the PR(1,2,2,1) encoding method to the elementary waveform of the encoded sequences, where delay operators D have a delay time of the encoded sequence cell width T.sub.b ; a low pass filter; an A/D converter for sampling and quantizing the equalized waveform sequence x(t); and a Viterbi decoder for comparing the A/D converter output {a.sub.i } with a particular expected value, and determining the most probable path as decoded sequence {A.sub.i }. The transfer function of PR(1,2,2,1) encoding well approximates the combined transfer function of the recording and reproducing means and the waveform equalizer, achieves strong suppression of interwaveform interference, and achieves high density recording. The Viterbi decoder has a long minimum free distance and an improved error correction rate.

Information recording and reproducing apparatus

A magneto-optical recording apparatus capable of maintaining decoding performance even if the recording density at the magneto-optical recording is high. The magneto-optical recording apparatus comprises a modulator for RLL (Run-Length Limited) encoding recording data, an NRZI encoder for NRZI-encoding a RLL code from the modulator, an equalizer for equalizing a read-out analog signal obtained from a magneto-optical recording medium into a waveform (1+D).sup.n (n is a positive integer) assuming that the delay time for one bit period of the read-out signal is D, a low pass filter, and a Viterbi decoder that uses the difference between a sample value obtained by quantizing an output from the low pass filter and an expected value obtained from a theoretical value of a data column to make the most probable path to be decoding data.

Growing community of inventors

Suwa, Japan

Michio Kobayashi