Teledyne LeCroy QPHY-10GBase-T - Manual (Page 24)

Test 6 - Transmitter Power Level
The purpose of this test is to verify that the power level of the transmitter is within the
conformance limits as defined in section 55.5.3.4 of the IEEE 802.3-2008 specification.
This test uses Test Mode 5.
W HAT I S M EASURED
The area of the averaged FFT of the differential signal C1-C2 is measured.
T EST M ETHODOLOGY
The Test Mode 5 signal is analyzed by taking an averaged FFT of the differential signal C1-C2.
At least 2000 waveforms are acquired to form the averaged FFT. When the average is
complete, the area of the FFT is calculated via parameter P1. The result is compared to the
PowerLevel value from the limit table in order to determine if the test passes.
D EFAULT P ASS C ONDITION :
The test passes if the result is between 3.2 dBm and 5.2 dBm.
Figure 11 –Transmitter Power Level Test Results
Shown on this screen:
• F1 = C1-C3
• F3 = Avg(F2), where F2 = FFT(F1) (creates an FFT averaged over multiple sweeps)
• P1 = area(F3)
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