A phase shifter comprises a substrate, a ground plane formed on a first surface of the substrate, a support structure positioned on a second surface of the substrate opposite the first surface, three parallel, non-co-planar microstrip lines supported by the support structure above the second surface...http://www.google.com.au/patents/US7417587?utm_source=gb-gplus-sharePatent US7417587 - Ferrite phase shifter and phase array radar system
