Quasi-optical millimetre wave oscillator & power combiner

The present interest in quasi-optical resonators is for CW and pulse power combining at short millimetric wavelengths where, owing to the highly overmoded cavity geometry, arrays of discrete gain elements may be accommodated on the mirror surfaces and the output powers combined in a single cavity mode. In order to accommodate significant numbers of source modules alternative resonator geometries utilising corner reflectors are also under investigation. The advantages of this arrangement are three-fold: (a) The roof reflector provides a greater surface area for supporting the active array (b) The resonator symmetry can now be maintained by using two spherical mirrors (c) More sophisticated output coupling arrangements can be employed as the end mirror is no longer required to support the array