Wideband 3 dB/90 degrees coupler in multilayer thick-film technology

A wideband 3 dB/90 degrees coupler based on multilayer thick-film technology is proposed. With reference to the well known Lange structure, the presented coupler is quite interesting in terms of realisability, and sensitivity with respect to technological limitations. In addition, no external operation, such as wire bonding, is needed, thereby resulting in good reproductibility.