Wideband balun structure

摘要

A balun structure is disclosed having positive and negative going signal paths coupled to a ninety degree hybrid. The positive signal path (44) has a circuit trace and a phase shaper structure (50) that provides three hundred and sixty degrees of phase shift at Port 1 of the hybrid. The negative going signal path (46) has a circuit trace and a second order phase shaper (58) that provides four hundred and fifty degrees of phase shift at Port 2 of the hybrid. Port 1 is coupled to Port 3 of the hybrid and functions as an output port. The first order phase shaper and the second order phase shaper compensate for the signal loss caused by a signal cable coupled to the output port and provide a frequency band from DC to at least 15 GHz and a transient response having less than ten percent pre-shoot.