Q-band Integrated Four Frequency Multiplier Studies

There are two ways to obtain millimeter band signal source. One is obtaineddirectly by some kinds of oscillators; the other is obtained by doubling microwaveband frequency signal. This paper presents theoretical analysis, circuit design of Qband multiplier which is uncommon in our country.In this paper we elaborately study many kinds of doubler circuits, then researchcharacters and applications of non-linear components. All of them comprises the baseof our theory and bring out a conference way to other kinds of multipliers. After thatwe make out a scheme of the forth multiplier and it includes microwave band doubler,amplifier and millimeter band doubler.Firstly, we design microwave band doubler based on classic theory of Marchandbalun. CAD technology is applied to simulate the doubler, which includes ananti-parallel diode pair. This method avoids blindfold debugging and save lots of timeand outlay. The microwave band frequency doubler employing beam-lead Schottkydiodes is developed. Input and output signal are isolated and harmonic component ofthe output signal is very low by using a unique planar balanced circuit structure. Thispaper presents the design of waveguide-to-microstrip probe transition in Q-band. Thetransition has low insertion loss in full Q-band. We not only simulate and measure theclassic impedance transform microstrip probe, but also research a new curvemicrostrip probe. Besides, we also design coaxial probe to prevent gas leak.Threekinds of MMIC are used as middle amplifier, millimeter band doublerd and outputamplifier. IC selecting, character analysis and DC circuit design are presented in thispaper. We make a Q band doubler according to the simulating results and measure it.It almost reaches what we have expected and can be used in expanding frequency ofmeasure system and local oscillators of receiver or simulator signal source oftransmitter.