The tests evaluate the voltage amplitudes, jitter values, rise/fall times and other signal characteristics. For each test a defined test signal must be generated by the DUT, e.g. a continuous pseudo-random signal has to be emitted. The easiest way to test the signal requirements is to define a test mask. The signals must not intersect with the mask in order to fulfill the specification. The 10Base-T tests are very often defined through a test mask, as you can see in the first figure. I want to mention some values: The Peak Differential Output Voltage must be between 2.2 V and 2.8 V. The Differential Output Voltage Harmonics must be greater than 27 dB and all Jitter values must be smaller than 22 ns. Very interesting is the twisted-pair model for 10Base-T, which must be used for some compliance tests. With the equivalent circuit based on lumped elements, it is possible to model multiple different transmission elements with just passive components. Depending on the PHY a linking partner is needed for 10Base-T compliance tests. You can download the Test Report of Colibri iMX6ULL as an example, where you can find all tests.
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