Verifying the accuracy of 2x-Thru de-embedding for unsymmetrical test fixtures

Due to its simplicity, the 2x-Thru test fixture de-embedding algorithm has been gaining acceptance by the test and measurement community. One common misconception of the 2x-Thru de-embedding algorithm is that it requires the test fixture to be symmetric on both sides of the DUT. To handle an unsymmetrical test fixture design, one can simply implement a separate 2x-Thru structure for each of the fixtures connecting to the DUT and thus, separate the problem into two symmetrical 2x-Thru structures. In this paper, we will leverage a kit of PCB test structures with coaxial adapters to validate the accuracy of 2x-Thru de-embedding algorithms for unsymmetrical test fixtures.