Corner-fed microstrip antenna element and arrays for dual-polarization operation

A systematic study on the dual-polarized corner-fed microstrip antenna element and arrays with thin single-layer structure is presented. The impedance matrices and S-parameters of the element and arrays are investigated by the proposed extended multiport network method (EMNM). The co- and cross-polarization patterns are also analyzed. It is shown that this kind of antenna element has an isolation about 10 dB higher than that of a conventional edge-fed square patch. A series of new dual-polarized arrays of corner-fed patches have been designed and analyzed based on the EMNM. The experimental results of five arrays indicate that these arrays achieve an isolation of 27∼38 dB with a maximum of higher than 28∼58 dB and cross-polarization level of lower than -23∼ -30 at boresight, which are substantially better than those of similar dual-polarized arrays of edge-fed patches. All theoretical results are in good agreement with experimental ones.