⎻
rsrq
:
The RSRQ or the Reference Signal Received Quality is a measurement that
indicates the quality of the received reference signal calculated using the RSRP and the
RSSI values described above.
3.5.4.2. Power and Quality of Signal
The RSRP and RSRQ parameters are typically the best indicators of signal strength. The values
of RSRP and RSRQ are returned as raw values (dB or dBm). Please see the table below for
signal strength estimates based on the raw values.
Returned RSRP Value
(Signal Power)
Estimated
Signal Strength
Returned RSRQ Value
(Signal Quality)
Estimated
Signal Strength
RSRP < -100 dBm
Marginal
RSRQ < -19.5 dB
Marginal
-100 dBm
≤
RSRP < -90 dBm
Fair
-19.5 dB
≤
RSRQ < -15 dB
Fair
-90 dBm
≤
RSRP < -80 dBm
Good
-15 dB
≤
RSRQ < -10 dB
Good
≥
-80 dBm
Excellent
≥
-10 dB
Excellent
For the example shown below, the RSRP is “Excellent” while the RSRQ is “Fair”.
3.5.5. Confirming Network Registration
If you successfully set up the PDP context and determined your signal strength is acceptable,
the next step is to confirm that you are registered with the network. Network registration should
have occurred automatically. Network registration acts like a handshake between the modem
and the cell tower, indicating that the SIM card successfully authenticated with the network and
the cell tower agrees that you are capable of joining its network. To confirm Network
Registration occured, enter the command below.
a. Query network registration status:
Command:
AT+CEREG?
Response:
+CEREG: <n>,<status>
Where
<n>
=[0,1,2,4] and
<status>
=[0,1,2,3,4,5]. The default is
<n>
=0. If network
registration was successful,
<status>
=1 or
<status>
=5, where a 1 indicates that you
PN 1002152 REV A
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