Modelling of mutual coupling in microstrip antenna arrays fed by microstrip line

The results of modelling of coupling between the rectangular microstrip patches in linear array are presented. The equivalent circuit in form of a combination of the transmission lines stubs is proposed. It is shown that such circuit well represents mutual coupling in narrow frequency band (4%). Two linear arrays were designed to verify the theory: first which includes proposed equivalent circuit and second one without the coupling (reference array). The results of measurements of VSWR and the radiation pattern are presented and compared with theory.