User manual

Chapter 2 - Managing a Single Device/Cell Site Survey Per Modulation Level Counters Page (SU and RB Only)
AlvariCRAFT Device Manager 95 User Manual
The Link Quality section enables to display the average quality of the wireless
link to the AU, using the dynamically updated average modulation level
measurements. The Link Quality Indicator (LQI) calculation is performed using
the following formula:
LQI = (0.9 x "Previous LQI") + (0.1 x "Last Successful Modulation Level").
Each successful transmission will be included in this average, by using the
modulation level at which the frame was successfully transmitted as the "Last
Successful Modulation Level".
In order to receive quick and reliable LQI measurements, there should be
sufficient traffic between the SU and the AU. It is recommended to have traffic of
at least 100 packets per second.
To activate a new Uplink Quality test, click on the Start button. The Last Uplink
Test Results displays the last results, rounded to the nearest integer. If Limited
Test is indicated in the Uplink Quality Indicator Status, it means that the
results may not indicate the true quality, as not all modulation levels from 1 to 8
are available. The limitation may be due to the HW of the unit (HW Revision A), or
the applicable parameters in the country code, or the configured Maximum
Modulation Level parameter.
The page includes also the following components:
Average Modulation
Level
This is the average modulation level (rounded to the nearest integer)
since the last time the Per Modulation Level counters were reset. The
average is calculated using the Tx Success count at each modulation
level as weights.
Average Received RSSI The average RSSI (in dBm) of received frames.
Polling Interval (sec) and
Apply button
The refresh interval for the displayed counters. Enter the required
polling interval and click on the Apply button to update it.
The range is 5 to 3600 seconds. The default is 5 seconds.
Reset Counters button Click on the button to reset all Per Modulation Level counters, the
Average Received SNR counter and the Average Modulation Level
counter.