Extended Unterminated Line (Eul) For Accurate And Efficient Crosstalk Measurement

Traditional crosstalk measurements require more ports on the test equipment, especially for differential configuration and are therefore costly. Another challenge is the need of perfect termination on the non-measurement ports, which is not practical in the actual implementation. In this paper, we introduce a novel crosstalk measurement method using the EUL (Extended Unterminated Line) structure. The test method overcomes the aforementioned shortcomings of the traditional techniques with minimum amount of test ports, and are suitable for non-50-ohm interconnects such as 40-Ohm for DDR or 85-Ohm for PCI Express. We report both simulation and measurement results to validate the EUL algorithm.