Aethra d2061 ユーザーズマニュアル
ADSL TESTER D2061
USER’S MANUAL
6. SMART STATUS
6.1. About this Chapter
This chapter gives you information of how to display and read the status of the
instrument and the tested interface.
instrument and the tested interface.
6.2. Reading the ADSL Access Status
The Smart Status™ menu contains various result displays like a live status report on
the modem. In particular the Smart Status allows displaying:
the modem. In particular the Smart Status allows displaying:
►
Number of bits assigned per tone.
►
Count of errors, events, or anomalies on the line.
►
Current and history status of any near-end and far-end alarms.
6.2.1. DMT Bits Allocation
The Bits graphic/table feature measures the bits per tone distribution used by the
modem to transmit the provisioned rate. It displays the number of bits assigned per
tone in either a graphic or table format.
modem to transmit the provisioned rate. It displays the number of bits assigned per
tone in either a graphic or table format.
During modem initialization, a signal to noise measurement is made for each tone; bit
distribution is then optimised to meet the desired bit rate.
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.
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.
The following illustration shows the Bit per Tone.
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CHAPTER 6 - SMART STATUS