Design of a Low-Loss E-band Self-Biased Waveguide Circulator for Space Applications

The development of next-generation space telecommunication systems relies on new frequency bands such as E-band or W-band. Circulators are key components in those systems but their size limits their use in application where size and weight are critical. In this paper, an E-band self-biased waveguide circulator is presented. The synthesis procedure is detailed and adapted to fit manufacturing constraints. EM simulations are run to validate the design before production. The realized circulator shows state-of-the-art performance with a minimum insertion loss of 0.37 dB and a maximum isolation level of 17.8 dB at 71.6 GHz without the need of magnets. Isolation level is better than 15 dB between 68.4 GHz and 74.2 GHz. This work opens the path to future E-band or W-band self-biased circulators, either in waveguide or planar technology.