Siemens M20 Terminal Technical Description page 87

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AT+CSQ Signal quality
Test command Response
AT+CSQ=? +CSQ: (list of supported <rssi>s), (list of supported <ber>) OK
Parameter
see execute command
Execute command Response
AT+CSQ TA returns received signal strength indication <rssi> and channel bit error rate <ber> from the ME.
+CSQ: <rssi>, <ber> OK
Parameter
<rssi>
<ber>
Reference Note
GSM 07.07
Version 8 dated 15.03.00
Receive level:
0 -113 dBm or less
1 -111 dBm
2...30 -109... -53 dBm
31 -51 dBm or greater
99 not known
Bit error rate:
0...7 as RXQUAL values in the table in GSM 05.08 section 8.2.4
99 not known
AT command interface
A
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