A circulator with a coplanar structure is designed and analysed using a three dimensional finite element method. Based on the proposed design, the circulator is fabricated with a YIG (Yttrium Iron Garnet). The thickness of YIG is only 65 μm. The design is planar and realized by stacking several layers, resulting in a potentially simple and low cost industrial process. Simulated results are better than measured ones but circulation is obtained around 9 GHz. Measured insertion loss is 5 dB and isolation is 36 dB giving interesting perspectives for the device.
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