Directional Couplers

Directional couplers sample a defined fraction of the power travelling in one direction along a line, which is how forward and reflected power are measured separately.

Keysight supplies this range. The specifications that matter are coupling factor, which sets how much signal reaches the sampled port, and directivity, which determines how well the coupler distinguishes forward from reverse travel. Directivity is the figure that limits the accuracy of any return loss measurement built around the coupler. Confirm frequency coverage, insertion loss on the main line and power handling, and check whether a dual directional coupler is needed to monitor both directions at once.