Frequency doubling diode

For the frequency doubling effect of diodes, there are frequency doubling relying on varactor diodes and frequency doubling relying on step (i.e. rapid) diodes. The varactor diode used for frequency doubling is called a variable reactor. Although the working principle of the variable reactor is the same as that of the varactor diode used for automatic frequency control, the structure of the reactor can withstand high power. A step diode, also known as a step recovery diode, has a short reverse recovery time trr when switching from conduction to shutdown. Therefore, its advantage is that the transition time to quickly turn off is significantly short. If a sine wave is applied to a step diode, the output waveform will be abruptly pinched off due to the short transition time (tt), resulting in the generation of many high-frequency harmonics.