| 摘要 |
PROBLEM TO BE SOLVED: To provide a device provided with filters that can set a frequency value indicating the pass frequency characteristics of the filters with high precision. SOLUTION: A frequency divider circuit 41 of a high frequency receiver 51 frequency-divides a sampling clock signal of analog/digital converters 18, 19 at a frequency division ratio according to a control signal T1 from a control signal generator 47 to generate a constant current reference signal with a frequency equal to a cut-off frequency of low-pass filters 14, 15 whose frequency characteristics are to be set. A phase shift circuit 42, a mixer 43, a low-pass filter 44, a DC amplifier circuit 45 and a constant current source 46 control the mixer 43 to provide an output of zero on the basis of the constant current reference signal and give an output signal from the DC amplifier circuit 45 to a constant current source 26 as an output signal from a control circuit 40. Thus, the constant current source 26 gives a current in response to the cut-off frequency to be set to the low-pass filters 14, 15 without the need for magnification adjustment.
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