Low Loss Low Cost Microstrip Millimeter Wave Switches at 94 GHz

In recent years both military (sensors, seekers) and commercial (automotive) millimeter waves applications have emerged which involve mass production. These applications usually require both good performance and very low cost. In this paper we present two types of SPST switches at 94 GHz, which were specifically designed for low cost with minimal sacrifice in performance. The components are intended for integration in a 94 GHz front end, and thus are constructed in mirostrip on 5 mil duroid substrate. An SPST reflective switch using commercial PIN diodes has an insertion loss of less than 2 db and a non-reflective SPST switch has a conversion loss of less than 3 db (including two microstrip-to-waveguide transitions with estimated loss of more than 0.5db). Both switches have an isolation of more than 30 db.