Sifos Technologies PhyView PVA-3000, Reference Manual

Page: 112 / 134

PVA-3000 Reference Manual
December 2, 2019 Sifos Technologies Page
112
5.3.2. 1000BaseT Transmission Test
The pva_tx_1000 test evaluates transmitted signal and interface characteristics of the DUT. All measurements are
always performed on each of the four pairs since 1000BaseT always uses 4 transmitters. Hence, there is no need to
sequence MDI and MDI-X connection polarities as there is for 100BaseTx.
The following transmitted signal and interface characteristics are directly evaluated per pair:

Wideband Tx Power Level (dB relative to nominal wideband 100BaseTx transmitter)

SNR (dB Signal / Residual Distortion)

Low Frequency PSD (20 kHz – 2 MHz, dB relative to nominal 100BaseTx spectrum)

Wide Band PSD (4 MHz – 100 MHz, dB relative to nominal 100BaseTx spectrum)

Pair Timing Skew (nsec timing offset per pair)

Bulk Return Loss (dB ratio of reflected to transmitted power)

Crosstalk (dB ratio of crosstalk power to transmitted power)
If the standard spreadsheet report is selected, the results of the PSD measurements will be used to estimate IEEE 802.3
peak-to-peak voltage levels (Vpp), test signal #1 droop (%), and test signal #1 template fit on a per-pair basis. The
measured parameters will be displayed in both tabular and graphical form, shown below in Section 5.5 .
During the 1000BaseT transmission test, PSD, Return Loss, and Crosstalk measurements will attempt to force the port-
under-test into a preferred link configuration of MDI, MASTER. Other measurements including Wideband Tx Power,
SNR, and Pair Timing Skew allow for any auto-negotiated link configuration at the port-under-test.
5.4. Receiver Tests
Receiver tests assess the behavior of a DUT’s receiver under varying, including “worst case” link conditions. The
concept of testing receivers with impairment was described earlier in Section 1.3.13. The PHY Performance Test
Suite fully takes advantage of that concept.
10/100/1000BaseT receivers universally must be designed to tolerate the types of insertion loss created by 100M of
Cat5 cable while also tolerating other forms of line impairment. All 10/100/1000BaseT receiver testing performed in
the PHY Performance Test Suite is done with
Line Loss impairment (see Section 2.2.8) applied.
Additional impairments are utilized during the receiver tests including:

Controlled Random Noise Insertion (see Section 2.2.9)

Transmit Level Control (see Section 2.2.11)

Transmit Slew Rate (see Section 2.2.11)

Controlled Transmit Frequency Offset (see Section 2.2.10)

Controlled Transmit Jitter (see Section 2.2.10)
Receiver testing can be performed for 10BaseT, 100BaseT, and 1000BaseT links.
Unlike transmission and interface measurements, which can be performed more-or-less directly using the signals
received by the test port, receiver testing is always an indirect measurement. Section 1.3.12 introduced the two
alternative measurements utilized in receiver testing:

Link Monitor (Link Stability)

Packet Flow
The advantages and disadvantages associated with each of these methods is explained in Section 1.3.12 and users
should be fully versed in that topic before selecting one method or the other. Each of the receiver tests supports
selection of
Link Monitor or Packet Flow as the measurement technique. Link Monitor only requires a single test
port connection to a DUT whereas by default, Packet Flow testing is performed using both test ports on a PVA-3102
test blade, or both ports of the PVA-3002 analyzer.
As fully automated tests, all receiver tests must always deal with some important tasks:

Assuring initial link success with new connection and each impairment

Assuring recovery from link drops

Managing timer intervals over which measurements are performed