A novel highly compact dual-band branch-line coupler utilizing left and right-handed technique

A novel dual-band coupler is proposed by utilizing microstrip coupled transmission lines and entering into combination with complementary split ring resonator (CSRR). A lucid equivalent L-C circuit is synthesized and simulated for the analysis and the initial design of this proposed dual-band resonator. Additionally, a novel technique is introduced to shift the two pass bands towards the lower microwave frequencies, and subsequently, reduce the size of suchlike components. A dual-band microwave component is analyzed, designed and simulated by this technique. The simulated dual-band BLC demonstrated the merits which are mentioned as follows: a compact size more than that of the previous ones and a ratio of less than 2 for the two operating frequencies.