Radio frequency circulators are provided. In one implementation, a radio frequency circulator includes a substrate. The substrate includes a magnetizable material. The substrate has a first surface and a second surface. The second surface opposes the first surface. The radio frequency circulator includes a patterned conductive layer disposed on the first surface of the substrate. The patterned conductive layer includes a plurality of ports coupled to a resonator structure. The resonator structure includes a plurality of peripheral extensions coupled to a microstrip junction. Each peripheral extension includes a plurality of open microstrip stubs and at least one channel connecting the plurality of open microstrip stubs. The plurality of peripheral extensions are arranged about the microstrip junction.