Wide Band Frequency Doubler

Conventional frequency multipliers using step-recovery-diodes operate on narrow or moderate instantaneous bands. However, multipliers operating on bandwiths of 10 to 15% of the nominal frequency are needed in local oscillator generators for frequency agile up and down converter applications. This paper describes a microstrip frequency doubler, using thin film microwave circuit technology, in which a pair of SRDs, pumped in phase opposition, generates power in the common output line at even harmonics only, mainly the second. Such a technique allows wide-band doublers to be designed, since they do not need a tuned output network, which is the most important bandwidth limiting factor in conventional circuits.