Chapter 3 - Commissioning

3.4Configuring the Subscriber Unit’s Maximum Modulation Level

This section describes how to configure the maximum modulation level for Subscriber Units.

NOTE

If the unit is associated with the AU, then the final configuration of the Maximum Modulation Level parameter may be performed remotely, for example, from the site of the AU or from another site.

To configure the Maximum Modulation Level:

1If the SNR of the SU at the AU is too low, it is recommended that you configure the Maximum Modulation Level parameter to a value that is lower than the maximum supported by the unit. This can decrease the number of retransmissions due to attempts to transmit at modulation levels that are too high for the actual quality of the link.

2Check the SNR of the SU at the AU. You can use Telnet to view the SNR values in the MAC Address Database, which can be accessed from the Site Survey menu. If the ATPC algorithm is not enabled in both AU and SU, the test should be done with the Initial Power Level at the SU configured to its maximum value. If the SNR is lower than the values required for the maximum modulation level according to Table 3-3, it is recommended that you decrease the value of the Maximum Modulation Level.

NOTE

The SNR measurement at the AU is accurate only when receiving transmissions from the applicable SU. If necessary, use the Ping Test utility in the Site Survey menu to verify data transmission.

3Configure the Maximum Modulation Level according to Table 3-3, using the typical SNR values. It is recommended that a 2 dB margin be added to compensate for possible measurement inaccuracy or variance in the quality of the link.

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BreezeACCESS VL System Manual

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Alvarion SW VERSION 5.1 system manual Configuring the Subscriber Unit’s Maximum Modulation Level