发明名称 |
MOBILE RADIO COMMUNICATION TERMINAL INCORPORATING ELECTRONIC WAVE CLOCK |
摘要 |
PROBLEM TO BE SOLVED: To correct time and to provide accurate time by incorporating a receiver with a long-wave standard electronic wave in a mobile radio communication terminal and achieving the function of an electronic wave clock. SOLUTION: A long-wave standard electronic wave is received by an antenna 1 for long wave and a reception low-noise amplifier(LNA) 2 for long wave, and a reference marker in a standard signal being received by a reception pulse extraction circuit 3 is detected and is sent to a time generation circuit 4 and a time difference measurement circuit 5 as a pulse signal. On the other hand, a clock 7 being generated from an oscillator 12 by an incorporated crystal oscillator is counted by a built-in clock and is sent to the measurement circuit 5 via a time signal generation circuit 6 for measurement. The difference between time from the standard electronic wave being received and time from the built-in clock is measured and is sent to a correction signal generation circuit 7, and a correction signal corresponding to the time difference is sent to the built-in clock, thus correcting time. Accurate time is displayed on a display 11 as an electronic wave clock also at the mobile radio communication terminal by the loop control. |
申请公布号 |
JP2000206276(A) |
申请公布日期 |
2000.07.28 |
申请号 |
JP19990002575 |
申请日期 |
1999.01.08 |
申请人 |
HITACHI LTD;HITACHI VIDEO & INF SYST INC |
发明人 |
KUROSAWA KAZUHITO;SOMA ATSURO;WATANABE HIDEAKI |
分类号 |
G04G5/00;G04R20/00;G04R20/08 |
主分类号 |
G04G5/00 |
代理机构 |
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代理人 |
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主权项 |
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地址 |
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