Experimental study of an injection locked gyro-BWO
Journal
IEEE International Conference on Plasma Science
Pages
173-
Date Issued
2000
Author(s)
Abstract
High power handling capability and broad-band frequency tunability of the gyrotron backward wave oscillator (gyro-BWO) have been demonstrated in a number of experiments. In Ref. 1, the injection locking technique was employed to achieve phase control and spectral purity. Here, we present further studies of a Ka-band injection-locked gyro-BWO, operating in the TE11 mode at the fundamental cyclotron frequency. The interaction length is 3 cm. The beam voltage and current are, respectively, 100 kV and 4 A with an estimated velocity ratio of 1. Contrary to our expectation, it is found that the output power increases with the locking power. This effect becomes more apparent as the free running frequency approaches the cutoff frequency (33.1 GHz). In the figure below, the locked output power is shown to be increased over the free running power (100 kW) by as much as 54% at a locking power of approximately 5% of the free running power. Reasons for such significant efficiency enhancement (from 25% to 39%) are not yet fully understood and are being investigated.
SDGs
Type
journal article