Design and implementation of microwave transistor amplifiers using two-section CCITLs

A microwave transistor amplifier in the conjugately characteristic impedance transmission line (CCITL) system is designed and implemented using terminated finite lossless reciprocal periodic structures consisting of multiple 2-section microstrip reciprocal lossless transmission lines (TLs). The 2-section TL unit cell is designed at Φ = 15°, the argument of Z0⁻ which is the characteristic impedance of the backward wave associated with CCITLs. The frequencies where simulated and measured |S21| peaks are found, are slightly below the designed operating frequency of 2.4 GHz. The measured |S21| profile is similar to that obtained from the simulation; however, the overall value is lower due to associated losses in supplementary components.