| 摘要 |
PURPOSE: To enable compensating the waveform distortion of a correlative output signal which is outputted from an SAW matched filter as against temp. change by changing the frequency of an intermediate frequency signal which is inputted to the SAW matched filter in accordance with surrounding temp. CONSTITUTION: The oscillation frequency of VCO 3a constituting a PLL circuit 3 is fixed by the frequency dividing rate setting of a variable frequency divider 3b and its setting is controlled by a control part 12. If surrounding temp. changes and a state becomes the one where a distortion can be generated in the correlative output signal of the SAW matched filter 5, surrounding temp. data at this time is transmitted from a temp. detecting part to the control part 12. The control part 12 reads frequency dividing rate setting data as against inputted surrounding temp. data from a memory part 10 and shifts the frequency rate as against the frequency divider 3b from present setting based on same data. The frequency dividing rate shift permits the oscillation frequency of VCO 3a to change. The frequency of the intermediate frequency signal from a frequency converting part 4 changes by the frequency change of VCO 3a. |
