1. Field of the Invention
This invention relates to frequency multipliers and more particularly to frequency multipliers producing odd harmonics at one output port and even harmonics at a second output port.
2. Description of the Prior Art
Varactor diodes, Schottky barrier diodes and single and dual gate field effect transistor (FET) devices are each capable of producing harmonics of an applied microwave fundamental frequency signal. In each case the device is operated in its non-linear region to generate the harmonics. FETs have an advantage relative to diodes of providing gain and in particular dual-gate FETs provide better conversion gain and dynamic range than do single gate FETs. An article entitled "Balanced Dual Gate GaAs FET Frequency Doublers" by Roger Stancliff (1981, IEEE International Microwave Symposium Digest, Los Angeles, June 1981, pp. 143-145) reported on a frequency doubler which utilizes two dual gate FETs, an in phase power divider, an in-phase power combiner and a 180.degree. delay which produces even harmonics while suppressing all odd harmonics including the fundamental.