Quectel EG12 not support frequency lock to select band at any tower.
Quectel EG12 support one and many Cell Lock's, you can enter max 20 of CellLock's and it select the one with the best signal and set it as primary-band.
Note: the CA are still automatic and we cannot force any of CA. We can only have enabled band's what we want to use and check the incoming SiB message from eNB by AT+QENG="neighbourcell".
EARFCN give us center of frequency specific band of our ISP,
PHY-CELLID give us a specific antenna at tower
Example is base at signals like this one, Cell-Monitor show us:
interface/lte/cell-monitor lte1
Columns: PHY-CELLID, BAND, EARFCN, RSRP, RSRQ, RSSI, AGE
PHY BA EARF RSRP RSRQ RSSI AG
64 B3 1675 -99dBm -10dB -71dBm 1s
64 B7 3350 -104dBm -8dB -77dBm 1s
70 B3 1675 -110dBm -20dB -81dBm 1s
70 B7 3350 -116dBm -19dB -90dBm 1s
90 B3 1675 -114dBm -20dB -81dBm 1s
90 B7 3350 -123dBm -20dB -92dBm 7s
222 B3 1675 -118dBm -20dB -83dBm 4s
403 B3 1675 -111dBm -20dB -81dBm 1s
420 B3 1675 -117dBm -20dB -84dBm 1s
436 B3 1675 -113dBm -20dB -83dBm 4s
453 B7 3350 -125dBm -20dB -93dBm 1s
502 B3 1675 -112dBm -19dB -81dBm 1s
502 B7 3350 -116dBm -18dB -88dBm 1s
Syntax:
[admin@Chateau] > interface/lte/at-chat lte1 input="at+qnwlock=\?" wait=yes
output: +QNWLOCK: "common/4g",<num of cells>,[[<freq>,<pci>],...]
OK
Disable Cell Lock:
interface/lte/at-chat lte1 input="at+qnwlock=\"common/4g\",0"
Query:
interface/lte/at-chat lte1 input="at+qnwlock=\"common/4g\""
1x CellLock:
interface/lte/at-chat lte1 input="at+qnwlock=\"common/4g\",1,1675,64"
2x CellLock's:
interface/lte/at-chat lte1 input="at+qnwlock=\"common/4g\",2,1675,64,1675,70"
3x CellLock's:
interface/lte/at-chat lte1 input="at+qnwlock=\"common/4g\",3,1675,64,1675,70,3350,64"