Abstract
Overmoded relativistic backward wave oscillators cannot preserve output mode purity, generating a number of ${\rm TM}_{0{ n}}$ modes in general. Until now, terminations for high power microwave (HPM) devices are only matched to a single operating mode. It is quite difficult to properly radiate a combination of ${\rm TM}_{0{ n}}$ modes using HPM antennas. In this paper, a novel efficient ${\rm TM}_{0{ n}}$ –TEM-mode converter is proposed. With the method of power dividing and field matching described, a mixture of ${\rm TM}_{01}$ , ${\rm TM}_{02}$ , and ${\rm TM}_{03}$ modes generated by an HPM device can be successfully converted into a pure coaxial circular waveguide TEM mode utilizing the outer and inner coaxial waveguide structure with an efficiency of over 99% at the center frequency. Such a mode transition will greatly improve the radiation efficiency of HPM antennas.
Sign-in/Register to access full text options 
Free) 
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a call
