| 摘要 |
An RF circuit includes a balun circuit comprised of a coaxial cable having a desired characteristic impedance and having a first port coupled to a first port of said RF circuit and a second port and a transformer circuit having a first port coupled to the second port of the balun. The transformer circuit is comprised of a pair of coaxial cables, each having a desired characteristic impedance and each having a ferrite coupled thereto. The interconnects between center conductors and outer conductors in the transformer are made symmetrical such that a resonance with a frequency determined by the inductance and capacitance of the coaxial cables does not occur, preventing any nulls in an insertion loss characteristic of the RF circuit. The ferrite is selected to act as a circuit element having an impedance characteristic which is higher than the impedance characteristic of the coaxial cable. |
