Design of broadband transitions from microstripto slotline

Practical limitations in the design of very broadband transitions from microstrip to slotline are due to the limited realisability of high characteristic impedance slotline stubs and low characteristic impedance microstrip stubs. It is shown how such limitations may be alleviated by the use of junctions of stubs. Two tandem connected transitions employing this idea exhibit, in the frequency band 1–10 GHz, an insertion loss less than 1.5 dB.