Active Dual-Band Power Divider and Active Quad-Plexer Based on Traveling Wave Amplification and D-CRLH Transmission Line

Abstract

A travelling wave structure with two novel functionalities is presented in this brief. The structure benefits from the nonlinear dispersion relation of dual-composite right/left-handed (D-CRLH) transmission line (TL). It consists of two distributed amplifiers (DAs) that have one common gate line and two drain lines. The conventional microstrip TL is used for gate line while the D-CRLH unit cells (UCs) are used to make the drain TLs. When the operating frequencies of D-CRLH TLs of both drain lines are the same, the structure acts as a directional dual-band active power divider (PD). The RF input signal depending on the input signal frequency, is divided into two forward or reverse output ports after amplification. If the D-CRLH TLs have different operating frequencies with no common band, the structure can act as an active quad-plexer or directional quad band amplifier. In this situation, four amplified signals with different frequency bands can be extracted from four different physical output ports. Analysis and design procedure of the structure is provided and a fabricated prototype is measured which shows a good agreement between the simulated results and the measurement results.