Ercogener GenLoc 354e, Руководство пользователя

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Descriptions and non-contractual illustrations in this document are given as an indication only.
ERCOGENER reserves the right to make any modifications.
Dct_427_02
6.4.1.4 The owner application
The GenLoc 354e contains your application.
Set the RS232 port of the DTE according to your parameters (speed, data bits, parity and stop bit).
Check the display and the dialogue with the GenLoc 354e according to your own characteristics.
6.5 Checking the quality of the GSM reception signal
The modem contains the EGM standard library (see the documents "EG_EGM_CL_xxx_yy" of
ERCOGENER); in this case, the modem will be able to make a call only if the received GSM signal is
powerful enough.
The command
AT+CSQ
allows to know the reception level (
rssi
) of the signal sent by the closest GSM Base
Transceiver Station (BTS), as well as the reception error code (
g
).
When the SIM card is inserted and the PIN code entered, the command
AT+CSQ
allows to measure the
signal from the BTS of the subscribed operator network.
This command cannot be used without the SIM card.
To check the quality of the GSM signal, do the following operations:
Use a communication software like Hyperterminal, enter the command
AT+CSQ
.
The response is in the following format:
+CSQ : <rssi>, <ber>
with:
<rssi>
= indicates the reception level,
<ber>
= receive bit error rate.
Check the returned value
<rssi>
with the help of the table below.
Table 55 : RSSI value
Value of <rssi> Gain in dbm Interpretation Value of <ber> Interpretation
0 -113 dbm Insufficient 0 to 7
See Standards ETSI
GSM 05.08
1 to 10 -111 to -95 dbm Insufficient
11 to 30 -93 to -53 dbm Sufficient
31 (max) -51dbm Perfect
99 Unknown/not detectable 99 Unknown/not detectable
The GSM modem works normally with a minimum
<rssi>
between 11 and 15.
Below 10, the signal level is insufficient; the modem cannot work depending on the geographical situation or
the vehicle mobility. Above 15, the signal is sufficient.
For more information about the AT commands, see the document "EG_EGM_CL_xxx_yy" of ERCOGENER.