| 摘要 |
<p><P>PROBLEM TO BE SOLVED: To provide a method and an apparatus for measuring time difference, and a time difference measuring program capable of measuring easily the time difference all the time, by comparing directly a time supplied from at least one monitored objective time source with a reliable standard time, and capable of securing thereby the reliability of the time supplied from the monitored objective time source. <P>SOLUTION: In this time difference measuring method, a time measuring command transmitted from a time supply device 6 via an optical fiber 2 is received, a reception timing signal expressing reception timing thereof is generated to be stored, a transmission timing signal expressing transmission timing when transmitting the time measuring command transmitted from the time supply device 6 via the optical fiber 2 is received, and the transmission timing signal is compared with the reception timing signal to calculate differential information through the optical fiber 2 between the time supply device 6 and a time difference measuring device 1. A standard time signal expressing the standard time transmitted from the time supply device 6 via the optical fiber 2 is received, and a data expressing a time difference between the monitored objective time source 5 and a standard time source is calculated, based on the standard time signal expressing the standard time, the differential information and a signal expressing a time transmitted from the monitored objective time source 5. <P>COPYRIGHT: (C)2005,JPO&NCIPI</p> |
