Miniaturized patch antenna for dual-frequency operation

In this paper, we present the design of a miniaturized dual frequency patch antenna. This design is based on the possibility to insert a low pass filtering structure in the basic resonator and on the effect of this structure on the fundamental resonance frequency of the patch. The reduction and filtering techniques combined allow a reduction of size of 70% with dual frequency such as 900 MHz/2 GHz. A good efficiency can be obtained at the two frequencies by choosing correctly the dimensions of the patch and the nature of the substrate.