Self-Calibration Procedures for Vector Network Analyzers on the Basis of Reflection Standards

The LRR method (Line, Reflect) and the extended LNN method (Line, Network) for the calibration of 4-channel-network analyzers are presented. These self-calibration procedures have the advantage that the calibration circuits are all of equal mechanical length in contrast to the well-known TRL method (Through, Reflect, Line). The TRL method needs a line-standard with a different length than the other calibration standards. For the LNN and LRR method it is thus not necessary to displace the connectors of the vector network analyzer during calibration in order to contact the calibration structures. The LNN and LRR calibration standards consist of objects which have to be placed at three consecutive positions. While the LNN obstacles have a transmission, the LRR obstacles are realized as reflective networks. In addition to the known LNN procedure an extended theory is presented here which accounts for different distances between the obstacles. The circuits are thus easy to realize. Measurement results are presented in order to verify the robust functionality of the methods.