| 摘要 |
<P>PROBLEM TO BE SOLVED: To properly perform tuning to a receiving standard radio wave signal even when transmission delay in a signal transmission path exists. <P>SOLUTION: A control means 13 controls delay means 10, 12 so that a phase of a first signal and a second signal are in the same phase by entering signals from a local oscillation means 7 to a phase comparison means 11 as each first signal and second signal through delay means 10, 12, referring an output signal of the phase comparison means 11 in a first state closing a tuning short circuit means 9, then, in a second state opening the tuning short circuit means 9, performs proper tuning by entering the signals from the local oscillation means 7 through the delay means 10, an antenna tuning means 1 and the delay means 12 as the first signal and the second signal to the phase comparison means 11, respectively, referring the output signal of the phase comparison means 11 and controlling tuning characteristics of the antenna tuning means 1 so that a phase difference between the first signal and the second signal is 90 degrees. <P>COPYRIGHT: (C)2008,JPO&INPIT |
