A novel dual‐band branch line coupler based on strip‐shaped complementary split ring resonators

In this article, a novel dual‐band branch line coupler is presented. The dual‐band operation is realized by the LH‐RH transmission line composed of strip‐shaped complementary split ring resonators (CSRRs) and series gap, which can produce LH band around 900 MHz and RH band around 1800 MHz. The performances of the designed device at two operating frequencies are demonstrated by simulated and measured results, which are in good agreement.