Digi IX20, Руководство пользователя

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Digi IX20 hardware reference IX20 LEDs
IX20 User Guide 25
The weighted dBm measurements are negative numbers, meaning the smaller negative values
denote a larger number. For example, a -85 is a better signal than -90.
Note See Signal quality bars explained for more information regarding how signal strength is
calculated and subsequently displayed via the LED indicators.
Ethernet Link and Activity
The LEDs on the WAN/ETH1 and ETH2 ports indicate that the Ethernet network interface is up and
there is activity on the network interface.
Left LED (on top of port connector)
n
Off : No Ethernet link detected.
n
Blinking amber : Indicates Ethernet traffic.
Right LED (on top of port connector)
n
Off : No Ethernet link detected.
n
Solid green : 10/100 Mbps link detected.
n
Solid amber : 1000 Mbps link detected.
Signal quality bars explained
The signal status bars for the Digi IX20 measure more than simply signal strength. The value reported
by the 4G LTE signal bars is calculated using an algorithm that takes into consideration the Reference
Signals Received Power (RSRP), the Signal-to-noise ratio (SNR), and the Received Signal Strength
Indication (RSSI) to provide an accurate indicator of the quality of the signal that the device is
receiving.
For 3G networks (including HSPA+) and 2G networks, the signal strength bars are determined by the
RSSI value.
4G LTE algorithms
For 4G LTE, the IX20 device determines the RSRP, SNR, and RSSI values separately and uses the
following algorithms to display the signal quality:
RSRP > -85, rsrp_bars=5
-95 < RSRP <= -85, rsrp_bars=4
-105 < RSRP <= -95, rsrp_bars=3
-115 < RSRP <= -105, rsrp_bars=2
-199 < RSRP <= -115, if we're connected to the cellular network, rsrp_bars=1,
if not rsrp_bars=0
If RSRP <= -199, the device uses the RSSI as the value with the same algorithm:
SNR >= 13, snr_bars=5
4.5 <= SNR < 13, snr_bars=4
1 <= SNR < 4, snr_bars=3
-3 < SNR < 1, snr_bars=2