Rectangular Waveguide Band-pass Filter With High Power Harmonic Suppression

Filter is one of the most common devices in the field of communication. In the field of low frequency and microwave circuit,there are many applications of filters such as radar, communication system. These systems play a role which can choose the required frequency, and suppress unwanted clutter signal.In the field of high frequency,Its special structure makes it has many models, and the parasitic passband of it has produced bigger effect, this effect is more obvious in the multiplexer and resistance to electromagnetic interference filter. So the success of restrain parasitic passband is one of the important directions of modern microwave devices research.This article mainly discussed is the suppression of parasitic passband in rectangular cavity filter technology.At the beginning of the article, I describe the working principle of microwave filter, and parasitic passband is illustrated by the equivalent circuit. This paper mainly introduces the circuit theory and the disappear mode filter working principle, and put forward the restrain parasitic passband solution:capacitive load rectangular filter. we overcome the shortcoming of small power capacity, and put forward the improvement plan.I make a detailed study to explore:for a single cavity, I analyze the capacitive loading process, the influence of the various parameters on the harmonic load metal columns and basal membrane to the cavity waveguide filter. After applying capacitance loading technology to achieve the purpose of inhibiting harmonic filter. I analyze its properties. Later in order to overcome the problem of low load power capacity, I innovative the input signal and output signal decomposition before input filter in order to overcome the problem of improving the overall power capacity of filter. At last, further bold idea to change harmonics suppressor power capacity is proposed.