Ultrawide-band transitions and new microwave components using double-sided parallel-strip lines

Double-sided parallel-strip lines have been used as a balanced transmission line to feed double-sided printed antennas or to fabricate microwave components such as balanced mixers. In this paper, ultrawide-band transitions from microstrip line to double-sided parallel-strip line are developed with 1-30-GHz bandwidth. New microwave components using double-sided parallel-strip lines are designed with good measured results. The double-sided parallel-strip line has an advantage of easy realization of low-impedance lines, which are important for many component designs.