Novel Miniaturized Equal/Unequal HMSIW Filtering Power Dividers Based on the Evanescent Mode Technique

Abstract

In this paper, three miniaturized equal/unequal filtering power dividers (FPDs) applying the half-mode substrate integrated waveguide (HMSIW) and metamaterial concepts are offered. The operational method of the presented structures is based on the theory of evanescent mode propagation. The stepped-impedance resonator (SIR) technique has been employed to reduce the dimension of the conventional complementary split ring resonator (CSRR) unit-cell. In this technique, the slot lines in the conventional CSRR are replaced by the stepped-impedance slot lines in the improved metamaterial unit-cell which is called SIR-CSRR unit-cell. By means of the SIR-CSRR unit-cell, three equal/unequal FPDs with arbitrary power-dividing ratio have been reported. Additionally, to further size reduction of the proposed FPDs, the HMSIW platforms are used. All of the proposed HMSIW PDs are designed at 2.4 GHz which are suitable for WLAN applications. For demonstration of the applied procedures in the proposed HMSIW FPDs, the suggested equal/unequal HMSIW FPDs have been fabricated and measured. A reasonable agreement between simulated and measured results has been achieved. The entire size of the suggested equal/unequal HMSIW FPDs is about 0.11 × 0.09 λ_g^2.