Alpha Technologies DSM3 for XM2 - Technical Manual - Manual (Page 35)

35 745-814-B8-001, Rev. C (03/2014)
4.0 Web Interface
4.11 Tools Menu – Constellation and Microreflections
The Web Page of the DSM3 Series Communications Modules provides some basic tools for analyzing
impairments on the DOCSIS network. The “Tools” menu selection on the Web page provides access to
both the Constellation and Microreflections pages.
Note: The Constellation and Microreflections tools provided on the DSM3 Series Web page are for basic
identification of common network impairments. Additional analysis may be required with industry standard
analyzers and tools to verify and resolve the cause of the impairment.
4.11.1 QAM Constellation Tool
The Constellation page provides a constellation view of the DOCSIS channel that may assist in
identifying and troubleshooting common network impairments.
Navigate the mouse pointer to the Tools menu item and select “Constellation” in the drop down
menu to open and start the Constellation page. The page will automatically refresh until the
samples remaining counter reaches 0. Clicking the Restart button refreshes the constellation tool,
and clicking the Stop button halts the analysis.
The number of samples can be changed from 100 (default) on the sampling control to either 150
or 50 for more or less sample rates. For User Name and Password refer to Section 4.3.1, Web
Interface Security Levels.
Fig. 4-17, QAM Constellation Tool
(data values shown for illustration purposes only)