The “load-thru” (LT) de-embedding technique for the measurements of mm-wave balanced 4-port devices

The differential-mode behavior of a balanced 4-port device can be characterized by simple 2-port measurements if baluns are placed at both the input and the output. But the traditional insertion loss technique is not able to fully de-embed the baluns. Therefore, we propose the “load-thru” de-embedding technique which uses the differential-mode characteristics of a balun to fully extract the complete differential-mode behavior of the DUT. Theoretical analysis and mm-wave measurement verifications are provided.