1000BASE-T/100BASE-TX/10BASE-T Physical Layer Compliance Tests Manual
Intel Confidential 41
100Base-TX Transmitter Return Loss
11 100Base-TX Transmitter Return Loss
ANSI Section 9.1.5
11.1 Test Purpose
To measure the transmitter return loss.
11.2 Specification
“The UTP... Active Output Interface shall be implemented such that the following return loss
characteristics are satisfied for each of the specified line impedances.
Greater than 16 dB from 2 MHz to 30 mHz
Greater than (16 - 20log(f/30 MHz)) dB from 30 MHz to 60 MHz [where f = frequency]
Greater than 10 dB from 60 MHz to 80 MHz
The impedance environment for the measurement of the UTP AOI return loss shall be 100 ± 15 Ω.
The impedance [environment] shall be nominally resistive, with a magnitude of phase angle less
than 3° over the specified measurement frequency range.”
1
11.3 Test Equipment
•
Network analyzer (50 KHz to 500 MHz range)
•
S-parameter test set (or transmission/reflection test set)
•
Host computer running gigconf.exe
11.4 Test Fixtures
•
100Base-TX balun test fixture (Appendix D.2)
•
BNC cable, with 50 Ω characteristic impedance (Appendix E)
•
Network analyzer calibration fixture (Appendix A.5)
•
CAT5 twisted pair cable (under 6 inches in length)
11.5 Test Procedure
1. Connect the test equipment and UUT as shown in Figure 11-1.
1. ANSI X3.263-1995, p 29-30.
To Next Page
Loading...
Need help?
General