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Mikio Nagahara

Mikio Nagahara, Yamagata-Mura JP

Patent application numberDescriptionPublished
20090096672POSITION DETERMINATION METHOD, POSITIONING DEVICE, AND ELECTRONIC INSTRUMENT - A position determination method includes: performing a positioning process that calculates a located position by performing positioning calculations using satellite signals; determining whether or not a convergence condition is satisfied based on current and preceding positioning results when the positioning process is performed, the convergence condition being specified as a condition for determining whether or not the positioning results of the repeated positioning processes have converged; and determining the located position calculated by the current positioning process to be an output position when the convergence condition is satisfied.04-16-2009
20100045516POSITIONING METHOD, POSITIONING DEVICE, AND ELECTRONIC INSTRUMENT - A positioning method that performs current position calculations and outputs a positioning result position includes searching for satellite signals transmitted from positioning satellites to acquire satellites, combining satellites among the acquired satellites to extract satellite sets used for positioning, performing first positioning calculations on each calculation-target satellite set among the extracted satellite sets using the satellite signals transmitted from the acquired satellites included in the calculation-target satellite set, performing second positioning calculations on each calculation-target satellite set among the extracted satellite sets using the satellite signals transmitted from the acquired satellites that are included in the calculation-target satellite set, but do not include a low-elevation-angle satellite, and determining whether or not a positioning result obtained using the calculation-target satellite set is appropriate based on the difference between a position calculated by the first positioning calculations and a position calculated by the second positioning calculations, the elevation angle of the low-elevation-angle satellite satisfying a given low elevation angle condition, and determining the positioning result position from the positions calculated by the first positioning calculations on the satellite sets for which the positioning result has been determined to be appropriate.02-25-2010
20100302097POSITION DETERMINATION METHOD, POSITIONING DEVICE, AND ELECTRONIC INSTRUMENT - A position determination method includes: performing a positioning process that calculates a located position by performing positioning calculations using satellite signals; determining whether or not a convergence condition is satisfied based on current and preceding positioning results when the positioning process is performed, the convergence condition being specified as a condition for determining whether or not the positioning results of the repeated positioning processes have converged; and determining the located position calculated by the current positioning process to be an output position when the convergence condition is satisfied.12-02-2010

Mikio Nagahara, Matsumoto JP

Patent application numberDescriptionPublished
20080246660PRESENT POSITION LOCATING METHOD, POSITIONING DEVICE, AND ELECTRONIC INSTRUMENT - Estimation calculations for calculating an estimated present position are performed twice corresponding to each satellite set. The estimated present position calculated by the second estimation calculations is determined to be a present position candidate corresponding to the target satellite set. In the first estimation calculations corresponding to the first satellite set, the calculated satellite position and estimated pseudo-range of each GPS satellite are stored in caches. In the second estimation calculations, the satellite position of each GPS satellite is read from the cache. In the first estimation calculations corresponding to the second or subsequent satellite set, the satellite position and the estimated pseudo-range of each GPS satellite are read from the caches, and the satellite position and the estimated pseudo-range of the GPS satellite of which the satellite position and the estimated pseudo-range have not been stored in the caches are calculated and stored in the caches. In the second estimation calculations, the satellite position of each GPS satellite is read from the cache.10-09-2008
20080246661FIRST OUTPUT POSITION CALCULATION METHOD, STORAGE MEDIUM, POSITIONING DEVICE, AND ELECTRONIC INSTRUMENT - In the first positioning, a positioning process that calculates the present position based on acquired GPS satellite signals (step A10-09-2008
20090040104PRESENT POSITION LOCATING METHOD - An evaluation point E of a present position candidate corresponding to each satellite set is calculated based on an a priori residual (APR) (APR value), a PDOP value, and the number of satellites of the target satellite set according to E=k02-12-2009
20100007557FIRST OUTPUT POSITION CALCULATION METHOD, STORAGE MEDIUM, POSITIONING DEVICE, AND ELECTRONIC INSTRUMENT - In the first positioning, a positioning process that calculates the present position based on acquired GPS satellite signals (step A01-14-2010
20100079335PRESENT POSITION LOCATING METHOD - An evaluation point E of a present position candidate corresponding to each satellite set is calculated based on an a priori residual (APR) (APR value), a PDOP value, and the number of satellites of the target satellite set according to E=k04-01-2010
20100141524TERMINAL DEVICE, POSITIONING METHOD, AND RECORDING MEDIUM - A terminal device includes a plurality of search channel sections which search for a positioning satellite, a candidate reception frequency calculation section which calculates a candidate reception frequency of a first acquisition target satellite by causing the search channel sections to perform the correlation accumulation process for a first accumulation time, a candidate frequency confirmation section which confirms reliability of the candidate reception frequency by causing the search channel sections to perform the correlation accumulation process for a second accumulation time longer than the first accumulation time, a final frequency calculation section which calculates a final frequency by causing the search channel sections to perform the correlation accumulation process for a third accumulation time longer than the second accumulation time, and a first difference calculation section which calculates a difference between an estimated synchronization frequency corresponding to each first acquisition target satellite and the final frequency.06-10-2010

Patent applications by Mikio Nagahara, Matsumoto JP