Getpacketstatus; G)Fsk Modem Description; G)Fsk Modulation Principle; Table 8-15: Getpacketstatus Command - Semtech LR1110 User Manual

8.3.7 GetPacketStatus

The command GetPacketStatus( ) gets the status of the last received packet. Since the returned values are modem
dependent, the description hereafter is valid only for the LoRa® modem.

Table 8-15: GetPacketStatus Command

Byte
Data from Host
Data to Host

Table 8-16: GetPacketStatus Response

Byte
Data from Host
Data to Host
• RssiPkt defines the average RSSI over the last packet received. RSSI value in dBm is –RssiPkt/2.
• SnrPkt is an estimation of SNR on last packet received. Expressed in two's complement format multiplied by 4. Actual
SNR in dB is SnrPkt/4
• SignalRssiPkt provides an estimation of RSSI of the LoRa® signal (after despreading) on last packet received. In two's
complement format [negated, dBm, fixdt(0,8,1)]. Actual Rssi in dB is -SignalRssiPkt/2
Additional information on the RSSI can be found in section

8.4 (G)FSK Modem Description

8.4.1 (G)FSK Modulation Principle

The (G)FSK modem is able to perform transmission and reception of 2-FSK modulated packets over a range of data rates
ranging from 0.6 kbps to 300 kbps.
Both the bit rate (Bitrate) and frequency deviation (Fdev) are directly configured using the command
SetModulationParams().
Additionally, in transmission mode, several shaping filters can be applied to the signal in packet mode or in continuous
mode. In reception mode, the user needs to select the best reception bandwidth depending on its conditions. To ensure
correct demodulation, the following limit must be respected for the selection of the bandwidth:
2 Fdev +
  BR  BWF 
Where the bandwidth BWF ranges from 4.8kHz to 467kHz.
The bandwidth must be chosen so that:
Bandwidth[DSB]
where the frequency error is two times the frequency error of the crystal oscillator used.
LR1110
User Manual Rev.1.0
UM.LR1110.W.APP March 2020
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0x02
Stat1
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 BR 
www.semtech.com
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RssiPkt SnrPkt
Section 8.7 "RSSI Functionality" on page
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