Service Manuals, User Guides, Schematic Diagrams or docs for : Agilent 5990-9346EN Stressing 1 GbE Receivers on the Physcial Layer - Application Note c20141103 [9]

<< Back | Home

Most service manuals and schematics are PDF files, so You will need Adobre Acrobat Reader to view : Acrobat Download Some of the files are DjVu format. Readers and resources available here : DjVu Resources
For the compressed files, most common are zip and rar. Please, extract files with Your favorite compression software ( WinZip, WinRAR ... ) before viewing. If a document has multiple parts, You should download all, before extracting.
Good luck. Repair on Your own risk. Make sure You know what You are doing.



Image preview - the first page of the document



>> Download 5990-9346EN Stressing 1 GbE Receivers on the Physcial Layer - Application Note c20141103 [9] documenatation <<

Text preview - extract from the document

Keysight Technologies
Stressing 1 GbE Receivers on the
Physical Layer




        Application Note




                   More eficient and effective
                   tests with a new generation
                   of test instruments
Introduction

     1000Base-T Ethernet, and the technical challenges
     it creates for design and test
     The standard for the 1000Base-T Ethernet (IEEE 802.3ab) describes data rates
     of 1 Gb/s over a star topology, over up to 100 meters of Category 5 (or better),
     unshielded, balanced, twisted-pair, copper cable.

     To make the 1000BASE-T physical layer standard as compatible as possible
     with existing standards, it reuses aspects of the existing IEEE 100BASE-TX,
     100BASE-T4, and 100BASE-T2 standards. In particular, the 125 Mbaud baseband
     signaling from 100BASE-TX, the use of all four twisted pairs simultaneously for
     full duplex transmission from 100BASE-T4, and the 5-level pulse amplitude
     modulation (PAM5) from 100BASE-T2. This enables dual-speed 100/1000 Ethernet
     physical layer implementations to reuse existing infrastructures. Cherry-picking
     elements from existing standards also helped reduce the time taken to develop
     the newer standard.

     Baseband signaling at a modulation rate of 125 Mbaud over each twisted pair
     matches the GMII clock rate of 125 MHz, as used for 100BASE-TX, and results
     in a symbol period of 8 ns. Each twisted pair also uses ive-level (-2, -1, 0, +1,
     +2), Pulse Amplitude Modulation (PAM5) to transmit 2-bits per symbol. The
     resulting data rate of 250 Mb/s in one direction over each twisted pair achieves
     a combined data rate of 1000 Mb/s. Furthermore, by using canceller symbols
     and magnetic hybrids (for echo cancellation), 1000BASE-T can optionally
     transmit and receive simultaneously on each twisted pair, to achieve full-duplex
     transmission at 2000 Mb/s.
03 | Keysight | Stressing 1 GbE Receivers on the Physical Layer - Application Note



The design implications for 1000BASE-T receivers
Gigabit Ethernet promises a cost effective migration to 1000BASE-T for installations
that are already running 10/100Base-T over Category 5 cabling. However, because
these installations were originally only speciied to 10Base-T or 100Base-T, this is also
a potential weakness. Inadequate cabling can introduce distortions, attenuation, noise
(including cross-talk and echoes that have not been properly removed by the hybrids),
and propagation delay, and delay skew between the different twisted pairs.




                                                        Distortion           Attenuation         Noise            Delay

     TDX                                                                                                                          RDX
                   T                                                                                                      R


                                           Hybrid                                                        Hybrid

                                                                                     Crosstalk
                       R                                                                                                      T



Figure 1: Effects of attenuation, distortion, noise and delays on transmission
04 | Keysight | Stressing 1 GbE Receivers on the Physical Layer - Application Note



Noise sources
                                                                                       Further noise environment speciications
The noise with which a receiver has to contend comes from a
                                                                                       Return loss
number of sources.
 

◦ Jabse Service Manual Search 2024 ◦ Jabse Pravopis ◦ onTap.bg ◦ Other service manual resources online : Fixya ◦ eServiceinfo