Seiko Epson Corporation

Hidekazu Maezawa

Toshikazu Akiyama

Junichi Otsuka

Akira Momose

Eiji Kinoshita

Shigeru Imafuku

Akiyoshi Nakamura

Koichiro Yano

Norio Teruuchi

Kazunori Shimoda

Kiyotaka Muraki

Kazunari Kobayashi

An electronic apparatus refers to location measurement information measured in the past at each time when the latest location measurement information is output from a location measurement module with a predetermined measurement period, if measurement accuracy is good and it is regarded that a direction change has been made, determines the latest location measurement information as saving 'necessary' and stores the information. If the measurement accuracy is no good or it is regarded that a positioning point shown by the latest location measurement information is an intermediate point during linear traveling, the latest location measurement information is not saved. Therefore, a data size to be saved is made smaller than that in related art and draining of a battery taken for writing of data is reduced.

Wearable electronic apparatus, data analyzer, and travel record control method

A location of a mobile unit is intermittently measured based on a GPS satellite signal. A halt start time zone (first halt determination region) is set based on the measured location of the mobile unit when the determination is started. An each time zone (second halt determination region) is updated and set by accumulated averaging processing (statistical processing) of results of location measurements in the past. Whether or not the halt state of the mobile unit is continued is determined using whether or not the newly measured location of the mobile unit is contained in any one of the set halt determination regions.

Halt continuation determination method and halt continuation determination device

An execution method of a position calculating circuit that calculates a position by receiving a satellite signal transmitted from a positioning satellite and that has an externally readable storage section includes: receiving a selection signal for selecting acquired information, which is information acquired from information obtained from the satellite signal, from the outside; selecting the acquired information on the basis of the selection signal; and storing the acquired information in the storage section and outputting a notice signal, which indicates that the acquired information has been obtained, when the acquired information selected from the satellite signal being received is obtained.

Execution method of position calculating circuit, position calculating circuit, operation control method of position calculating circuit, host device, and electronic apparatus

A method of determining an initial position in executing a positioning calculation based on satellite signals from positioning satellites, includes: (a) executing position converging calculation based on the satellite signals using each of a plurality of first candidate positions as a provisional initial position; (b) selecting at least one second candidate position from the first candidate positions based on a calculation result of the position converging calculation; and (c) selecting the initial position from one of the second candidate positions using the satellite signals.

Initial position determination method, positioning method, and positioning apparatus

A terminal device receives satellite signals from a plurality of satellite positioning system (SPS) satellites and locates a position. The terminal device periodically calculates a first drift dfof a local oscillator using a reference frequency Hr, calculates a search range of the satellite signal using the first drift df, calculates a second drift dfof the local oscillator using a reception frequency of the satellite signal, calculates a reference frequency error &#x3b2; which is an error of the reference frequency by calculating a difference between the first drift dfand the second drift df, and calculates an error correction value &#x3b2;av of the reference frequency by subjecting a plurality of the reference frequency errors &#x3b2; to a statistical process.

Method of acquiring error correction value of reference frequency, terminal device, and recording medium

The present invention relates to a small portable information processing apparatus. A GPS unit ( ) is attachable to and detachable from a rear surface of a portable information terminal ( ), so that the GPS unit ( ) can be mounted on the rear surface of the portable information terminal ( ) to make it serviceable only when necessary, thus improving convenience. Power is supplied to the GPS unit ( ) only when an antenna unit ( ) is set in a serviceable state. This prevents the exhaustion of a battery.

Growing community of inventors

Shiojiri, Japan

Hidekazu Maezawa