An Asymmetric Tandem Coupler with Impedance Matching Elements for 12.5–25 GHz Operation

This letter presents a GaAs Monolithic Microwave Integrated Circuit (MMIC) implementation of an asymmetric, multisection coupler providing 10 dB of coupling range with low ripple over a frequency range of 12.5 to 25 GHz. Measurements of the manufactured coupler found acceptable performance characteristics from 10 to 32.5 GHz. The presented coupler was designed in a tandem configuration and utilized an asymmetric structure with impedance matching elements utilized in the interconnecting transmission lines between tandem sections.