To provide a time accuracy measuring apparatus capable of measuring accuracy of time based on standard time information in units of milliseconds.
A radio wave including frequency information synchronized in a standard time is received, a receiving edge signal Srec obtained by extracting a rising edge of a demodulated pulse is generated, and by using a plurality of monitoring timers 55-n capable of setting mutually different monitoring periods on the basis of a reference pulse signal Sref of a fixed period, whether or not a receiving edge signal appears in each monitoring period is monitored. By repeatedly performing division and resetting of a monitoring period selected based on the monitored result, a one-second signal Sair is extracted with accuracy higher than a received radio wave including noise and the accuracy of time to be measured is measured in units of milliseconds by detecting an error from the timing of the one-second signal.
| JPS54135572 | ELECTRONIC WATCH WITH ACOUSTIC DEVICE |
SUMIDA TETSUAKI
TADA YOSHINORI
| JP2006270542A | 2006-10-05 | |||
| JP2010025651A | 2010-02-04 | |||
| JP2007292613A | 2007-11-08 | |||
| JP2005249632A | 2005-09-15 | |||
| JP2009180655A | 2009-08-13 | |||
| JP2008241354A | 2008-10-09 |
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