Rectangular Waveguide Test Fixture for SIW Component and Circuit Measurements

A rectangular waveguide (RWG) test fixture for the characterization of substrate integrated waveguide (SIW) components and circuits is reported. First, the design of the test fixture is introduced with a detailed model of its RWG to SIW transition designed for operation at microwave frequency in the WR51 frequency band. Then, its physical implementation is presented together with its validation asing a SIW transmission line. As new threats are emerging, especially for defense and aerospace microwave systems, the assessment of SIW component and circuit power handling limitations becomes necessary. This test fixture has been designed in this purpose as its RWG interconnects allow high-power test.