| 摘要 |
PROBLEM TO BE SOLVED: To miniaturize a reception device by allowing a reception antenna to sweep a control voltage in an AFC adjustment period and change a local oscillation frequency and outputting the optimum control voltage value corresponding to the maximum value of the pulse width time of video signal change to a local oscillator. SOLUTION: A trigger signal that is generated at every transmission of radar and an azimuth signal that is updated every time a radar antenna rotates by a unit angle are inputted to a control voltage sweeping/optimum value retention circuit 10 and a gate circuit 4. The control voltage sweeping/optimum value retention circuit 10 supplies a control voltage for changing an oscillation frequency to a local oscillator 8 while an antenna azimuth is in gate period. The gate circuit 4 takes out only a video signal while the control voltage changes from itself and outputs it to a pulse width conversion circuit 5. Then, the control voltage sweeping/optimum value retention circuit 10 obtains the average value of data in the same azimuth based on pulse width information being stored in a storage circuit 7, calculates data with stable azimuth versus pulse width, and performs the optimum value retention processing of the control voltage. |
