Method and apparatus for increasing the high frequency sensitivity response of a sampler frequency converter

摘要

A method and apparatus comprising a sampler frequency converter having a first and a second diode. A local oscillator having a frequency FLO, a step recovery diode and a balun transformer are used for providing positive and negative sampling pulses to the diodes for sampling an input signal applied to the diodes having a frequency FIN. An output signal is provided by the diodes having a frequency FOUT which is defined by the relationship FOUT¦FIN+/-NxFLO¦ where N is an integer harmonic number 1, 2, 3 . . . and the output signal has an amplitude which varies as a function of (sin x)/x where x=FIN. A bandpass filter is provided which is responsive to the output signal for filtering a predetermined band of frequencies therefrom and a bias circuit is provided for forward biasing the diodes so that the frequency FIN of said input signal at which nulls occur in said (sin x)/x relationship occur at a lower frequency after said biasing than before said biasing.