Electric field enhancement and power absorption in microwaveTR-switches

An analytical and numerical investigation is made of electric field enhancement due to scattering of an incident plane wave by a biconical conductor. An application to microwave transmit-receive switches (TR) shows that field enhancement factors of the order of 20 to 40 are to be expected in the region close to the keep-alive contacts. An analysis of the microwave absorption by a small plasma sphere located in the vertex of the biconical conductor is also presented, showing that the plasma sphere absorbs a significant fraction of the incident power independently of the plasma size. This explains the observed absorption properties during the turn-on phase of TR switches