Split rings-based differential transmission lines with common-mode suppression

Summary form only given, as follows. A novel microstrip differential transmission line with common-mode suppression is presented, implemented by etching complementary split ring resonators (CSRRs). For differential signals, the symmetry of the structure cancels the electric field axial to the CSRRs, and these particles have no effect on signal. However, the CSRRs are activated under common mode excitation, with the result of a stop-band. For the prototype, over 20 dB suppression of common-mode is achieved over a range 1.18–1.74 GHz.