User Manual

Table Of Contents
SARA-R4/N4 series-AT Commands Manual
UBX-17003787 - R11
7Network service
Page 42 of 308
7.3Extended signal quality +CESQ
+CESQ
SARA-R404M SARA-R410M-01B SARA-R410M-02B SARA-R410M-52B SARA-R412MModules
SARA-N4
Syntax PIN required Settings saved Can be aborted Response time Error referenceAttributes
full No No No - +CME Error
7.3.1Description
Returns the received signal quality and level:
If the current serving cell is not a GERAN cell, the <rxlev> and <ber> parameters are set to value 99
If the current serving cell is not a UTRA FDD cell, the <rscp> and the <ecn0> parameters are set to 255
If the current serving cell is not an E-UTRA cell, the <rsrq> and <rsrp> parameters are set to 255.
The Reference Signal Received Power (RSRP) is a LTE specific measure that averages the power received
on the subcarriers carrying the reference signal. The RSRP measurement bandwidth is equivalent to a
single LTE subcarrier: its value is therefore much lower than the total received power usually referred
to as RSSI. In LTE the RSSI depends on the currently allocated bandwidth, which is not pre-determined.
Therefore the RSSI is not useful to describe the signal level in the cell.
7.3.2Syntax
Type Syntax Response Example
Action AT+CESQ +CESQ: <rxlev>,<ber>,<rscp>,<ecn0
>,<rsrq>,<rsrp>
OK
+CESQ: 99,99,255,255,20,80
OK
Test AT+CESQ=? +CESQ: (list of supported <rxlev>s),
(list of supported <ber>s),(list
of supported <rscp>s),(list
of supported <ecn0>s),(list
of supported <rsrq>s),(list of
supported <rsrp>s)
OK
+CESQ: (0-63,99),(0-7,99),(0-96,
255),(0-49,255),(0-34,255),(0-97,
255)
OK
7.3.3Defined values
Parameter Type Description
<rxlev> Number Received Signal Strength Indication (RSSI):
0: less than -110 dBm
1..62: from -110 to -49 dBm with 1 dBm steps
63: -48 dBm or greater
99: not known or not detectable
<ber> Number Bit Error Rate (BER):
0..7: as the RXQUAL values described in GSM TS 05.08 [28]
99: not known or not detectable
<rscp> Number Received Signal Code Power (RSCP):
0: -121 dBm or less
1..95: from -120 dBm to -24 dBm with 1 dBm steps
96: -25 dBm or greater
255: not known or not detectable
<ecn0> Number Ratio of received energy per PN chip to the total received power spectral density:
0: -24.5 dB or less
1..48: from -24 dB to -0.5 dBm with 0.5 dB steps
49: 0 dB or greater
255: not known or not detectable
<rsrq> Number Reference Signal Received Quality (RSRQ):
0: -19 dB or less
1..33: from -19.5 dB to -3.5 dB with 0.5 dB steps
34: -3 dB or greater