GB1223147A - Improvements in or relating to microwave power supply arrangements - Google Patents

Abstract

1,223,147. Gunn effect oscillators. TELEFUNKEN PATENTVERWERTUNG G.m.b.H. 24 May, 1968 [27 May, 1967], No. 24845/68. Heading H3T. In a power supply arrangement having a volume effect semi-conductor device G connected to a signal source S, of predetermined microwave frequency, via a circulator Z, the semi-conductor device G is included in a circuit R which is resonant at the predetermined frequency S and controllable D.C. bias source U is connected to apply a bias to the semi-conductor device so as to control the power fed back from the device G to an output branch A of the circulator. As shown the Gunn effect device G is biased so that its resistance matches the resistance of the source S. This only allows a small part of the source S signal to be reflected from the device G to the circulator and out of branch A. If the bias voltage U is increased this increases the mismatch between the resistance of the device (which changes) and that of the source S so that more of the signal S is reflected by the device G to the output A. If the bias U is further increased above the critical value for the device G, oscillations are produced by the device. The oscillations are synchronized by the incoming microwave signal S and the output power now available at A is increased beyond that which source S can deliver. The resonant circuit R may be a cavity resonator or resonating chamber or an oscillation circuit of a strip line.