Development of a broadband slotted-waveguide antenna at X-band for radiometric applications

Abstract

In recent years a slotted-waveguide antenna in Ka band has been developed at DLR for a hybrid radiometric imaging system, combining the method of aperture synthesis and frequency scanning. The challenge of such antennas is to generate maximum angular scan angle with minimum bandwidth regarding to real-time imaging. At Ka band roughly 26° scan range at 9 GHz bandwidth has been achieved. Now it is expected that the rate - scan angle range per bandwidth – can be increased at lower microwaves. Consequently a new slotted-waveguide antenna shall be developed around X band in order to investigate scanning capabilities with respect to the radiometric requirements of minimum losses, maximum radiation efficiency, and maximum angular resolution.