| 摘要 |
<p>In a high frequency signal level determining device for determining the input signal level of a high frequency signal, an AGC circuit (31) performs, based on an intermediate frequency signal as obtained by frequency converting the received high frequency signal, an automatic gain control of the intermediate frequency signal, by using both an RFAGC value for controlling the gain of the high frequency signal and an IFAGC value for controlling the gain of the intermediate frequency signal, such that the output level of the intermediate frequency signal becomes substantially constant. A controller (50) measures, in advance, both first relationship data of the RFAGC value to the input signal level of the received high frequency signal and second relationship data of the IFAGC value to the input signal level of the received high frequency signal. When the high frequency signal to be measured is received, the controller (50) measures the RFAGC and IFAGC values again and determines, based on the measured RFAGC and IFAGC values, the input signal level of the received high frequency signal by use of the first and second relationship data measured in advance.</p> |
