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7.2.15 SetRssiCalibration
Command SetRssiCalibration(...) sets the gain offset for the on-chip power estimation:
Table 7-19: SetRssiCalibration Command
Byte
Data from Host
Data to Host
Byte
Data from Host
Data to Host
•
TuneGx(...) (arguments 2 to 10): RSSI Gain Tune values. A tune is a 4-bit signed value, where 1lsb = 0.5dB.
Table 7-20: Gain Tune Values
Tune
0
1
value (dBm)
0
0.5
•
GainOffset: Global offset added to the Gain Tune values. The offset is a 12-bit signed value, where 1lsb = 0.5dB.
The power seen by the LR1121 analog front-end is affected by external components such as the matching network, or RF
switches. An incorrect RSSI results in a sensitivity degradation in (G)FSK mode and an incorrect gain selection in LoRa and
GFSK mode. An incorrect gain can result in a missed detection (packet loss) or decreased resistance to interference.
By default, the chip is calibrated for the 868-915MHz band on the LR1121 EVK.
Table 7-21: Recommended Values for Reference EVK
Frequency
below 600MHz
0
from 600MHz
0
to 2GHz
above 2GHz
2030
LR1121
User Manual
Rev 1.1
UM.LR1121.W.APP
Mar 2023
0
1
0x02
0x29
Stat1
Stat2
7
Tune
G13hp2(7:4)
G13hp4(7:4)
G13hp1(3:0)
G13hp3(3:0)
0
2
3
4
5
1
1.5
2
2.5
12
12
14
0
1
2
2
2
3
3
6
7
6
4
3
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2
3
Tune
Tune
G5(7:4)
G7(7:4)
G4(3:0)
G6(3:0)
IrqStatus
IrqStatus
(31:24)
(23:16)
8
9
Tune
Tune
G13hp6(7:4)
G13hp5(3:0)
0
6
7
8
9
3
3.5
-4
-3.5
3
4
4
3
6
4
5
4
4
6
4
14
12
14
12
4
5
Tune
Tune
G9(7:4)
G11(7:4)
G8(3:0)
G10(3:0)
IrqStatus
IrqStatus
(15:8)
(7:0)
10
11
Tune
Gainoffset
G13hp7(3:0)
(15:8)
10
11
12
13
-3
-2.5
-2
-1.5
6
6
6
6
5
5
6
6
12
12
12
8
Proprietary & Confidential
6
Tune
G13(7:4)
G12(3:0)
0
12
Gainoffset
(7:0)
14
15
-1
-0.5
6
6
6
6
7
6
8
9
9
59 of 130
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