Скачать или смотреть Ceramic patch antenna tuning

The untuned patch antenna already has a resonant frequency. This frequency is determined by the width of the patch. The frequency is too high. How can we reduce this frequency without widening the patch?

In step 2 we extend the path of the RF current without widening the patch. By adding the notches, the current must take a new longer path. The resonant frequency of the antenna becomes lower.

In the 3rd step we force the RF current to flow around the corner. Therefor we cut the corners by 45 degrees. As a result we get a second resonance frequency which is again too high.

In step 4 we extend the path of the RF current again without widening the patch. By inserting the notches the current has to take a new longer way. The resonance frequency of the antenna is expected to be lower.