Signal quality bars explained

The signal status bars for the Digi 6300-CX measure more than simply signal strength. The value reported by the 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 6300-CX 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 
-99 < SNR <= -3, if we're connected to the cellular network, snr_bars=1, if not 
snr_bars=0

Once the snr_bars and rsrp_bars values are determined, the device uses the lesser of the two as the reported signal a bars.

3G algorithm

For 3G, the 6300-CX determines RSSI signal strength:

RSSI > -80, bars=5 
-90 < RSSI <= -80, bars=4 
-100 < RSSI <= -90, bars=3 
-106 < RSSI <= -100, bars=2 
RSSI <= -106, if we're connected to the cellular network, bars=1, if not bars=0

bars is then reported as the signal strength bars.

2G algorithm

For 2G, the 6300-CX determines RSSI signal strength:

RSSI > -80, bars=5 
-89 < RSSI <= -80, bars=4 
-98 < RSSI <= -89, bars=3 
-104 < RSSI <= -98, bars=2 
RSSI <= -104, if we're connected to the cellular network, bars=1, if not bars=0

bars is then reported as the signal strength bars.