Test Port Cable Instability and VNA Measurement Errors

Test port cables are often analyzed to determine the quality of their stability performance. However, the actual impact of their instability often is overlooked or not accounted properly. Cable stability measurements using traditional methods, such as using a short, do not correlate to the impact of cable instability on DUT measurements. An alternative method is presented that use ECal to analyze cable stability that provides a greater degree of insight on how DUT measurements are impacted by cable instability. In addition, methods to minimize the impact of cable instability are examined.