Serpentine Guard Trace to Reduce Far-end Crosstalk and Even-Odd Mode Velocity Mismatch of Microstrip Lines by More than 40%

A serpentine guard trace located between two microstrip transmission lines reduced the peak far-end crosstalk voltage and the difference in propagation delay times between the even and odd mode signals by more than half of those of the no guard case, respectively, without the PCB area overhead. This reduction was achieved by increasing mutual capacitance without changing mutual inductance.