Design of microwave wave gain equalizer using microstrip shorted SIR

Gain equalizer is often used to adjust the output gain of traveling wave tubes (TWT) or high power solid state amplifiers. Traditionally, the resonant branch of microwave gain equalizer is a single short or open microstrip line. However, this structure is hard to reduce the reflection coefficient and, it cannot control the bandwidth easily. In this paper, the microwave gain equalizer is fulfilled by microstrip stepped impedance resonator (SIR) with thin film resistance integrated. This structure could easily overcome the defects in traditional equalizer. The measurement results show that the equalization curve meet requirements well, proved this structure is practical and effective.