To check the RSSI signal quality on a modem issue the following AT command to the
modem:
AT+CSQ
Followed by the enter key. The modem should respond with:
+CSQ: <x>,<y>
OK
where xx is the signal strength of the antenna, and yy is the bit error rate in percent.
Typical values are as follows:
The modem's bit error rate will only be detectable during data transfers and will be not
known when the modem is idle.
PN 1002634 REV 1
© NimbeLink Corp. 2021. All rights reserved.
20
Values of <y>
Bit Error Rate (in percent)
0
Less than 0.2%
1
0.2% to 0.4%
2
0.4% to 0.8%
3
0.8% to 1.6%
4
1.6% to 3.2%
5
3.2% to 6.4%
6
6.4% to 12.8%
7
More than 12.8%
99
Not known or not detectable
Values of <x>
Relative Signal Strength
0 – 9
Poor: <= -95 dBm
10 – 14
OK: -93 dBm to -85 dBm
15 – 19
Good: -83 dBm to -75 dBm
20 – 30
Excellent: -73 dBm to -53 dBm
31
Excellent: -51 dBm or greater
99
Not known or not detectable
