Multiband reduced-size patch antenna by employing a modified DMS-spur-line combo technique

In this article, a simple but effective combination of DMS and spur-lines is achieved to obtain a multiband patch antenna. The advantage of this technique is the simplicity to elaborate and the good performance compared to other methods where nulls are present in the radiation pattern at the main lobe. The antenna presents five resonant frequencies, which are fully controllable by modifying the dimensions of the defected microstrip structures and spur-lines, obtaining the characteristic directive radiation pattern and maximum gain above 6 dBi in all bands.