| 摘要 |
PURPOSE:To narrow an oscillation frequency band, by applying a variable reactance element with a signal proportional to variations in the bias voltage of an IMPATT diode. CONSTITUTION:When a pulse (a) is applied from the terminal 3 of an IMPATT diode 1, its junction part temperature Tj rises within the pulse period with time and when the pulse current is ceased, it falls. Therefore, the voltage V of the IMPATT diode 1 appearing at the terminal 3 has a breakdown voltage rising according to a rise in the junction part temperature Tj. An oscillation frequency (f), on the other hand, decreases with time within the pulse period. As the voltage of a varactor diode 4 is raised, its junction capacity decreases and the oscillation frequency increases. For this purpose, the voltage variations DELTAV(t) of the IMPATT diode 1 are detected and applied to the varactor diode 4 through a variable reactance element control circuit 7, suppressing variations DELTAf(t) in oscillation frequency. |
