Microwave Antennas & RF-Sensors

General RF Sensors MMW Devices


Despite large effort and progress of varies groups in designing receiving systems for space applications and other fields of interest at millimeter waves, there is still the need of improvement regarding sensitivity and dynamic range of implemented devices. Due to the specific demand in our group towards the measurement of LC tunable Relectarrays, we focus on the design of mixers and detectors in the frequency range of millimeter waves and beyond. Aiming for systems that are also capable of operating at room temperature, the choice of devices are planar Schottky diodes. For the implementation and supply of Schottky diodes we stay in close cooperation with ACST GmbH.

W Band Transition from Rectangular Waveguide to Microstrip at 77 GHz

Design, Optimization, Realization

Millimetre wave devices like power sources and antennas often use rectangular waveguides (e.g. WR10 for W Band). On the other hand planar components, e.g. Schottky Diodes, have to be put on planar circuits, e.g. Microstrip. To be able to use both structures in one device transitions are developed.

With a fixed back short in the WR10 waveguide and a radial stub on Microstrip the transition can directly be used for impedance matching. The contact to ground at both ends of the Microstrip line is due to a further design, where the transition is applied. A back-to-back structure is commonly used to verify transitions.

  • Back-to-back structure in split block technique (CST Microwave Studio)
  • Power Flow (CST Microwave Studio)
  • Realized waveguide in split block technique (lower part)
  • Part of realized MSL structure on Quartz substrate (signal layer)