Aethra d2061 用户指南

QUICK GUIDE 

D2061 ADSL TESTER 

 

The feature allows to display immediately modem, line and instrument status. 

In particular the Smart Status™ allows to display: 

► 

Number of bits assigned per tone 

► 

G.826 quality measurement results 

► 

Count of errors, events, or anomalies on the line. 

► 

ATM cells statistics 

► 

Current and history status of any near-end and far-end alarms at 

ATM level. 

► 

Vdc on the line. 

The Bits graphic/table feature measures the bits per tone distribution used by the 
modem to transmit the provisioned rate and displays the number of bits assigned 
per tone either in a graphic or table format. 

 

During modem initialisation, a signal to noise measurement is made for each 
tone; bit distribution is then optimised to meet the desired bit rate.  

Each tone can support a theoretical maximum of 15 bits. During operation, the bit 
distribution may be adjusted to optimise bandwidth. 

 

The modems constantly monitor the signal to noise ratio for each tone. If a tone 
degrades in quality, a bit swap command can be sent to adjust the amount of bits 
assigned to that particular tone. 

 

These bits may be added to a different tone or taken out completely.  

 

 

 

 

 

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