Data Sheet

Datasheet
iM980A
iM980A_Datasheet_mcf88.docx, v1.2 Page 5
3. LoRa Modulation Technique
The iM980A uses Semtech’s LoRa proprietary spread spectrum modulation
technique. This modulation, in contrast to conventional modulation
techniques, permits an increase in link budget and increased immunity to in-
band interference. It achieves sensitivities 8 dB better than FSK modulation.
LoRa also provides significant advantages in both blocking and selectivity,
solving the traditional design compromise between range, interference
immunity and energy consumption.
3.1 Channel Frequencies
The iM980A uses the following channel set up specified by LoRaWAN [2]:
• Uplink (Tx) – 64 channels numbered 0 to 63 utilizing LoRa 125 kHz BW
varying from DR0 to DR3, using coding rate 4/5, starting at 902.3 MHz
and incrementing linearly by 200 kHz to 914.9 MHz
• Uplink (Tx) – 8 channels numbered 64 to 71 utilizing LoRa 500 kHz BW at
DR4 starting at 903.0 MHz and incrementing linearly by 1.6 MHz to 914.2
MHz
• Downlink (Rx) – 8 channels numbered 0 to 7 utilizing LoRa 500 kHz BW at
DR8 to DR13) starting at 923.3 MHz and incrementing linearly by 600 kHz
to 927.5 MHz
3.2 Data Rates and Spreading Factors
The iM980A uses the following data rates and spreading factors specified by
LoRaWAN [2]:
Data Rate
Settings
Indicative Physical Bit Rate [bit/s]
0
LoRa: SF10 / 125 kHz
980
1
LoRa: SF9 / 125 kHz
1760
2
LoRa: SF8 / 125 kHz
3125
3
LoRa: SF7 / 125 kHz
5470
4
LoRa: SF8 / 500 kHz
12500
5:7
For future use
8
LoRa: SF12 / 500 kHz
980
9
LoRa: SF11 / 500 kHz
1760
10
LoRa: SF10 / 500 kHz
3900
11
LoRa: SF9 / 500 kHz
7000
12
LoRa: SF8 / 500 kHz
12500
13
LoRa: SF7 / 500 kHz
21900
14:15
For future use
Table 3-1: Data Rates and Spreading Factors