Menus and Parameters
4.2.5.3.1Continuous Average SNR/RSSI Display
The Continuous Average SNR Display option displays continuously updated information regarding the average quality of the received signal, using Signal to Noise Ratio (SNR) and Received Signal Strength Indication (RSSI) measurements.
The average RSSI is calculated using the formula:
NewAvgRSSI = (PrevAvgRSSI*HistWeight) + CrtRSSI*(1 – HistWeight ), where:
NewAvgRSSI = New Average RSSI
PrevAvgRSSI = Previous Average RSSI
CrtRSSI = RSSI of the current packet
HistWeight = History Weight
The History Weight is given by the next formula:
HistWeight = 0.9 / ( PastTime / 2SNR_Memory_Factor + 1 ), where
PastTime = time between the current packet and previous packet, in seconds
SNR_Memory_Factor = the Average SNR Memory Factor configurable parameter (see Average SNR Memory Factor on page 186.
The SNR_Memory_Factor can be
The same formula is used also for calculating Average SNR (SNR values are used instead of RSSI values).
Click the Esc key to abort the test.
4.2.5.3.2Continuous Noise Floor Display
The Continuous Noise Floor Display option displays continuously updated information regarding the average noise floor in the wireless link.
Click the Esc key to abort the test.
4.2.5.3.3Continuous UpLink Quality Indicator Display
The Continuous UpLink Quality Indicator Display option displays continuously updated information regarding 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 formula:
LQI = (0.9 x ”Previous LQI”) + (0.1 x ”Last Successful Modulation Level”).
Operation and Administration
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