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LG02 LoRa Gateway User Manual
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13.
FAQ
13.1
Why there is 433/868/915 version LoRa part?
Different country has different rules for the ISM band for using the LoRa. Although the LoRa chip
can support a wide range of Frequency, we provide different version for best tune in the LoRa
part. That is why we provide different version of LoRa.
13.2
What is the frequency range of LG02 LoRa part?
The chip used in the LoRa part is:
Version
LoRa IC
Support Frequency
Best Tune Frequency
433
Semtech SX1278
Band2(LF): 410 ~525Mhz
Band3(LF): 137 ~175Mhz
433Mhz
868
Semtech SX1276
Band1(HF): 862 ~1020Mhz
868Mhz
915
Semtech SX1276
Band1(HF): 862 ~1020Mhz
915Mhz
User can set the LoRa within above frequency range in the software.
13.3
What does “Limited support on LoRaWAN”?
The base requirement to fully compatible with LoRaWAN protocol requires the gateway support
8 channels. The LG02 only support two channels and can only support limited LoRaWAN protocol.
Below are limitations:
1/ It works only on one frequency at a time
. It can support multiply end nodes, but all end
nodes must transmit data at the same frequency so the LG02 can receive it. For example: if the
End node transmits at 868.1Mhz, The LG02’s RX setting must be 868.1Mhz so to receive this
packet.
2/ It works only for one DR at a time.
DR specifies the Spreading Factor and Bandwidth. In LG02,
even the rx frequency match , if DR doesn’t match, it still can’t get the sensor data.
3/ LoRaWAN compatible issue
In LoRaWAN protocol, the LoRaWAN end nodes send data in a hopping frequency. Since LG02
only supports one single frequency, it will only be able to receive the packets sent from the same
radio parameters (frequency & DR) in LG02.
For example, in EU868, a standard LoRaWAN device may send the data in eight frequencies with
different Frequency & SF, such as:
LMIC_setupChannel(0, 868100000, DR_RANGE_MAP(DR_SF12, DR_SF7), BAND_CENTI); // g-band
LMIC_setupChannel(1, 868300000, DR_RANGE_MAP(DR_SF12, DR_SF7B), BAND_CENTI); // g-band
LMIC_setupChannel(2, 868500000, DR_RANGE_MAP(DR_SF12, DR_SF7), BAND_CENTI); // g-band
LMIC_setupChannel(3, 867100000, DR_RANGE_MAP(DR_SF12, DR_SF7), BAND_CENTI); // g-band
LMIC_setupChannel(4, 867300000, DR_RANGE_MAP(DR_SF12, DR_SF7), BAND_CENTI); // g-band
LMIC_setupChannel(5, 867500000, DR_RANGE_MAP(DR_SF12, DR_SF7), BAND_CENTI); // g-band
