Application of complementary split ring resonators for size reduction in patch antenna arrays

In this paper, a novel technique for reducing the dimensions of patch antennas and their arrays is presented. The procedure uses complementary split ring resonators (CSRRs) for increasing the slow-wave effect on the radiator, and therefore augmenting its electrical length, which implicates the modified antenna gets a lower physical dimension than a conventional one for a given frequency. Led by the use of CSRRs, the patches may be closer to each other, without affecting the side lobes magnitude either the directivity of the array compared to a conventional one. As an example, a 4 × 1 patch array was designed and its total area was 40% smaller compared to a conventional one, considering the same design conditions with and without CSRRs. The gain, directivity, and coupling of the prototype were not affected.