Solution to GW TEM-Circular Polarized TE₁₁Mode Converter Design for High Frequency Bands

The solution utilized to design a compact transverse electromagnetic mode (TEM)-CPT (circular polarized TE11) mode converter with high power handling capability and high efficiency, especially at high frequency bands is proposed in this paper. The analysis shows that increasing the quantity of the arms of the converter could make the converter work under overmoded state. The problem that the power capability of the converter working at high frequency bands is low will be addressed. To verify the feasibility of this solution, simulations and experiments on a 20 arms converter are carried out, and the results show that the converter would convert the TEM mode into CPT mode efficiently in a 2-3 free wavelengths longitudinal size and that the power capability is in gigawatt (GW) class. Moreover, this kind of converter can also be utilized in the design of GW TEM phase shifter, whether at low or high frequency bands, which plays a key role in the power combining technology.