| 摘要 |
The clock system (100) corrects the instant time using a signal transmitted from a stationary satellite (10). In the clock system, a high-frequency-signal transmitted from the stationary satellite is converted to an intermediate-frequency-signal by an analogue-signal-processing-circuit (12), then converted into a digital signal, and finally decoded to a digital signal by a digital-signal-processing-circuit (14). A CPU (15) of the system calculates the stationary-satellite-time out of time data included in the signal transmitted, further the CPU converts it to a co-ordinated universal time (UTC). The clock system corrects the time of a clock circuit (18) with the UTC and displays it on a display (19). As a result, a user of the system at a fixed point on Earth can always receive the time data from the same satellite, so that the clock system can keep time with high accuracy. |
