Both RAK831 and RAK2245 get less than 50% of uplink packets from endpoints

Hi,

I’ve got a RAK2245 Pi HAT (AS923) and a RAK831 LoRa/LoRaWAN Developer Kit (with a converter board)(AU915), and I installed each on Respberry Pi 3 B+.

I ran the latest firmware (RAK2245&RAK831_based_on_Raspbian_OS_for_RPI3_V4.1.0_20191202) and tried point-to-point communication to them from my other LoRa endpoints (Seeeduino LoRaWAN, Dragino LoRa HAT+GPS, and Reyax rylr896).

I saw that both gateways can only receive less than 50% of packets sent from each one of those endpoints. I verified that by stopping the ttn-gateway service in the gateway and ran the start.sh at /opt/ttn-gateway/packet_forwarder/lora_pkt_fwd instead. I use the AS923 global config file and the sending frequencies I’ve tried are 923.6 and 924.2 MHz. The sending intervals I tried is between 1 to 4 seconds. The physical distance between an endpoint and a gateway is less than 3 meters.

I’ve also tested using /opt/ttn-gateway/lora_gateway/util_pkt_logger and enabled DEBUG_HAL, and I saw that the packet losses are not due to CRC error, because the CRC-error packet would still be logged. I looked at the code it seems that lgw_receive() just didn’t get many of the packets.

The following I attached the output of /opt/ttn-gateway/packet_forwarder/lora_pkt_fwd/lora_pkt_fwd.

Please advice what I shall do to avoid uplink packet losses. Thank you.

Sincerely,

Chao

lgw_board_setconf:427: Note: board configuration; lorawan_public:1, clksrc:1
lgw_rxrf_setconf:476: WARNING: NOT A VALID TX NOTCH FILTER FREQUENCY [126000..250000]Hz
lgw_rxrf_setconf:488: Note: rf_chain 0 configuration; en:1 freq:923600000 rssi_offset:-166.000000 radio_type:2 tx_enable:1 tx_notch_freq:0
lgw_rxrf_setconf:488: Note: rf_chain 1 configuration; en:1 freq:924600000 rssi_offset:-166.000000 radio_type:2 tx_enable:0 tx_notch_freq:0
lgw_rxif_setconf:607: Note: LoRa 'multi' if_chain 0 configuration; en:1 freq:-400000 SF_mask:0x7e
lgw_rxif_setconf:607: Note: LoRa 'multi' if_chain 1 configuration; en:1 freq:-200000 SF_mask:0x7e
lgw_rxif_setconf:607: Note: LoRa 'multi' if_chain 2 configuration; en:1 freq:0 SF_mask:0x7e
lgw_rxif_setconf:607: Note: LoRa 'multi' if_chain 3 configuration; en:1 freq:200000 SF_mask:0x7e
lgw_rxif_setconf:607: Note: LoRa 'multi' if_chain 4 configuration; en:1 freq:400000 SF_mask:0x7e
lgw_rxif_setconf:607: Note: LoRa 'multi' if_chain 5 configuration; en:1 freq:-400000 SF_mask:0x7e
lgw_rxif_setconf:607: Note: LoRa 'multi' if_chain 6 configuration; en:1 freq:-200000 SF_mask:0x7e
lgw_rxif_setconf:607: Note: LoRa 'multi' if_chain 7 configuration; en:1 freq:0 SF_mask:0x7e
lgw_rxif_setconf:581: Note: LoRa 'std' if_chain 8 configuration; en:1 freq:-100000 bw:2 dr:2
lgw_rxif_setconf:637: Note: FSK if_chain 9 configuration; en:1 freq:200000 bw:3 dr:50000 (50000 real dr) sync:0xC194C1
lgw_start:823: Note: calibration started (time: 2300 ms)
lgw_start:844: Note: calibration finished (status = 191)
Info: Initialising AGC firmware...
Info: putting back original RADIO_SELECT value
*** Beacon Packet Forwarder for Lora Gateway ***
Version: 4.0.1
*** Lora concentrator HAL library version info ***
Version: 5.0.1;
***
INFO: Little endian host
INFO: found global configuration file global_conf.json, parsing it
INFO: global_conf.json does contain a JSON object named SX1301_conf, parsing SX1301 parameters
INFO: lorawan_public 1, clksrc 1
INFO: no configuration for LBT
INFO: antenna_gain 0 dBi
INFO: Configuring TX LUT with 16 indexes
INFO: radio 0 enabled (type SX1257), center frequency 923600000, RSSI offset -166.000000, tx enabled 1, tx_notch_freq 0
INFO: radio 1 enabled (type SX1257), center frequency 924600000, RSSI offset -166.000000, tx enabled 0, tx_notch_freq 0
INFO: Lora multi-SF channel 0>  radio 0, IF -400000 Hz, 125 kHz bw, SF 7 to 12
INFO: Lora multi-SF channel 1>  radio 0, IF -200000 Hz, 125 kHz bw, SF 7 to 12
INFO: Lora multi-SF channel 2>  radio 0, IF 0 Hz, 125 kHz bw, SF 7 to 12
INFO: Lora multi-SF channel 3>  radio 0, IF 200000 Hz, 125 kHz bw, SF 7 to 12
INFO: Lora multi-SF channel 4>  radio 0, IF 400000 Hz, 125 kHz bw, SF 7 to 12
INFO: Lora multi-SF channel 5>  radio 1, IF -400000 Hz, 125 kHz bw, SF 7 to 12
INFO: Lora multi-SF channel 6>  radio 1, IF -200000 Hz, 125 kHz bw, SF 7 to 12
INFO: Lora multi-SF channel 7>  radio 1, IF 0 Hz, 125 kHz bw, SF 7 to 12
INFO: Lora std channel> radio 1, IF -100000 Hz, 250000 Hz bw, SF 7
INFO: FSK channel> radio 1, IF 200000 Hz, 125000 Hz bw, 50000 bps datarate
INFO: global_conf.json does contain a JSON object named gateway_conf, parsing gateway parameters
INFO: gateway MAC address is configured to 0000000000000000
INFO: server hostname or IP address is configured to "0.0.0.0"
INFO: upstream port is configured to "1700"
INFO: downstream port is configured to "1700"
INFO: downstream keep-alive interval is configured to 10 seconds
INFO: statistics display interval is configured to 30 seconds
INFO: upstream PUSH_DATA time-out is configured to 100 ms
INFO: packets received with a valid CRC will be forwarded
INFO: packets received with a CRC error will NOT be forwarded
INFO: packets received with no CRC will NOT be forwarded
INFO: GPS serial port path is configured to "/dev/ttyAMA0"
INFO: Reference latitude is configured to 10.000000 deg
INFO: Reference longitude is configured to 20.000000 deg
INFO: Reference altitude is configured to -1 meters
INFO: fake GPS is disabled
INFO: Auto-quit after 20 non-acknowledged PULL_DATA
INFO: found local configuration file local_conf.json, parsing it
INFO: redefined parameters will overwrite global parameters
INFO: local_conf.json does not contain a JSON object named SX1301_conf
INFO: local_conf.json does contain a JSON object named gateway_conf, parsing gateway parameters
INFO: gateway MAC address is configured to B827EBFFFE7470FD
INFO: packets received with a valid CRC will be forwarded
INFO: packets received with a CRC error will NOT be forwarded
INFO: packets received with no CRC will NOT be forwarded
INFO: [main] TTY port /dev/ttyAMA0 open for GPS synchronization
INFO: [main] concentrator started, packet can now be received

INFO: Disabling GPS mode for concentrator's counter...
INFO: host/sx1301 time offset=(1586573817s:465704µs) - drift=13421416µs
INFO: Enabling GPS mode for concentrator's counter.

WARNING: [gps] GPS out of sync, keeping previous time reference
WARNING: [gps] GPS out of sync, keeping previous time reference

##### 2020-04-11 02:57:07 GMT #####
### [UPSTREAM] ###
# RF packets received by concentrator: 0
# CRC_OK: 0.00%, CRC_FAIL: 0.00%, NO_CRC: 0.00%
# RF packets forwarded: 0 (0 bytes)
# PUSH_DATA datagrams sent: 0 (0 bytes)
# PUSH_DATA acknowledged: 0.00%
### [DOWNSTREAM] ###
# PULL_DATA sent: 1 (0.00% acknowledged)
# PULL_RESP(onse) datagrams received: 0 (0 bytes)
# RF packets sent to concentrator: 0 (0 bytes)
# TX errors: 0
# BEACON queued: 0
# BEACON sent so far: 0
# BEACON rejected: 0
### [JIT] ###
# SX1301 time (PPS): 2672312
src/jitqueue.c:448:jit_print_queue(): INFO: [jit] queue is empty
### [GPS] ###
# Valid time reference (age: 1 sec)
# no valid GPS coordinates available yet
##### END #####

INFO: End of upstream thread
WARNING: failed to close GPS successfully
INFO: concentrator stopped successfully
INFO: Exiting packet forwarder program

Hi Chao. The latest firmware for RAK2245 and RAK831 for RPi is here https://github.com/RAKWireless/rak_common_for_gateway Please update.
As you state that you use AU915 and AS923 and their base frequency channels are different, can you check that you use same frequency plans on the Nodes and the Gateways?

Hi Velev,

Thanks. I followed your words and updated the firmware to the latest version on https://github.com/RAKWireless/rak_common_for_gateway
And I tested with RAK2245 and two LoRa endpoints. I ensured that all of them operate at 923.6 MHz, and for the RAK2245 I chose the AS923 configuration.

Unfortunately the RAK2245 now completely stopped receiving packets…
BUT at the same time I succeeded in making one endpoint keep receiving the data sent by the other 100% of time…
The sending endpoint is Reyax rylr896 and the receiving endpoint is Dragino LoRa GPS HAT, all configured to operate at 923.6 MHz.

I really have no idea why now the RAK2245 stopped working anymore…

Here is the log of lora_pkt_fwd (I have stopped the ttn-gateway.service first):

lgw_board_setconf:427: Note: board configuration; lorawan_public:1, clksrc:1
lgw_rxrf_setconf:476: WARNING: NOT A VALID TX NOTCH FILTER FREQUENCY [126000..250000]Hz
lgw_rxrf_setconf:488: Note: rf_chain 0 configuration; en:1 freq:923600000 rssi_offset:-166.000000 radio_type:2 tx_enable:1 tx_notch_freq:0
lgw_rxrf_setconf:488: Note: rf_chain 1 configuration; en:1 freq:924600000 rssi_offset:-166.000000 radio_type:2 tx_enable:0 tx_notch_freq:0
lgw_rxif_setconf:607: Note: LoRa 'multi' if_chain 0 configuration; en:1 freq:-400000 SF_mask:0x7e
lgw_rxif_setconf:607: Note: LoRa 'multi' if_chain 1 configuration; en:1 freq:-200000 SF_mask:0x7e
lgw_rxif_setconf:607: Note: LoRa 'multi' if_chain 2 configuration; en:1 freq:0 SF_mask:0x7e
lgw_rxif_setconf:607: Note: LoRa 'multi' if_chain 3 configuration; en:1 freq:200000 SF_mask:0x7e
lgw_rxif_setconf:607: Note: LoRa 'multi' if_chain 4 configuration; en:1 freq:400000 SF_mask:0x7e
lgw_rxif_setconf:607: Note: LoRa 'multi' if_chain 5 configuration; en:1 freq:-400000 SF_mask:0x7e
lgw_rxif_setconf:607: Note: LoRa 'multi' if_chain 6 configuration; en:1 freq:-200000 SF_mask:0x7e
lgw_rxif_setconf:607: Note: LoRa 'multi' if_chain 7 configuration; en:1 freq:0 SF_mask:0x7e
lgw_rxif_setconf:581: Note: LoRa 'std' if_chain 8 configuration; en:1 freq:-100000 bw:2 dr:2
lgw_rxif_setconf:637: Note: FSK if_chain 9 configuration; en:1 freq:200000 bw:3 dr:50000 (50000 real dr) sync:0xC194C1
lgw_start:823: Note: calibration started (time: 2300 ms)
lgw_start:844: Note: calibration finished (status = 183)
WARNING: problem in calibration of radio A for image rejection
Info: Initialising AGC firmware...
Info: putting back original RADIO_SELECT value
*** Beacon Packet Forwarder for Lora Gateway ***
Version: 4.0.1
*** Lora concentrator HAL library version info ***
Version: 5.0.1;
***
INFO: Little endian host
INFO: found global configuration file global_conf.json, parsing it
INFO: global_conf.json does contain a JSON object named SX1301_conf, parsing SX1301 parameters
INFO: lorawan_public 1, clksrc 1
INFO: no configuration for LBT
INFO: antenna_gain 0 dBi
INFO: Configuring TX LUT with 16 indexes
INFO: radio 0 enabled (type SX1257), center frequency 923600000, RSSI offset -166.000000, tx enabled 1, tx_notch_freq 0
INFO: radio 1 enabled (type SX1257), center frequency 924600000, RSSI offset -166.000000, tx enabled 0, tx_notch_freq 0
INFO: Lora multi-SF channel 0>  radio 0, IF -400000 Hz, 125 kHz bw, SF 7 to 12
INFO: Lora multi-SF channel 1>  radio 0, IF -200000 Hz, 125 kHz bw, SF 7 to 12
INFO: Lora multi-SF channel 2>  radio 0, IF 0 Hz, 125 kHz bw, SF 7 to 12
INFO: Lora multi-SF channel 3>  radio 0, IF 200000 Hz, 125 kHz bw, SF 7 to 12
INFO: Lora multi-SF channel 4>  radio 0, IF 400000 Hz, 125 kHz bw, SF 7 to 12
INFO: Lora multi-SF channel 5>  radio 1, IF -400000 Hz, 125 kHz bw, SF 7 to 12
INFO: Lora multi-SF channel 6>  radio 1, IF -200000 Hz, 125 kHz bw, SF 7 to 12
INFO: Lora multi-SF channel 7>  radio 1, IF 0 Hz, 125 kHz bw, SF 7 to 12
INFO: Lora std channel> radio 1, IF -100000 Hz, 250000 Hz bw, SF 7
INFO: FSK channel> radio 1, IF 200000 Hz, 125000 Hz bw, 50000 bps datarate
INFO: global_conf.json does contain a JSON object named gateway_conf, parsing gateway parameters
INFO: gateway MAC address is configured to 0000000000000000
INFO: server hostname or IP address is configured to "0.0.0.0"
INFO: upstream port is configured to "1700"
INFO: downstream port is configured to "1700"
INFO: downstream keep-alive interval is configured to 10 seconds
INFO: statistics display interval is configured to 30 seconds
INFO: upstream PUSH_DATA time-out is configured to 100 ms
INFO: packets received with a valid CRC will be forwarded
INFO: packets received with a CRC error will NOT be forwarded
INFO: packets received with no CRC will NOT be forwarded
INFO: GPS serial port path is configured to "/dev/ttyAMA0"
INFO: Reference latitude is configured to 10.000000 deg
INFO: Reference longitude is configured to 20.000000 deg
INFO: Reference altitude is configured to -1 meters
INFO: fake GPS is disabled
INFO: Auto-quit after 20 non-acknowledged PULL_DATA
INFO: found local configuration file local_conf.json, parsing it
INFO: redefined parameters will overwrite global parameters
INFO: local_conf.json does not contain a JSON object named SX1301_conf
INFO: local_conf.json does contain a JSON object named gateway_conf, parsing gateway parameters
INFO: gateway MAC address is configured to B827EBFFFE1C3397
INFO: packets received with a valid CRC will be forwarded
INFO: packets received with a CRC error will NOT be forwarded
INFO: packets received with no CRC will NOT be forwarded
INFO: [main] TTY port /dev/ttyAMA0 open for GPS synchronization
INFO: [main] concentrator started, packet can now be received

INFO: Disabling GPS mode for concentrator's counter...
WARNING: [gps] could not get GPS time from GPS
INFO: host/sx1301 time offset=(1586615661s:497722µs) - drift=-1092219526µs
INFO: Enabling GPS mode for concentrator's counter.

WARNING: [gps] could not get GPS time from GPS
WARNING: [gps] could not get GPS time from GPS
WARNING: [gps] could not get GPS time from GPS
WARNING: [gps] could not get GPS time from GPS
WARNING: [gps] could not get GPS time from GPS
WARNING: [gps] could not get GPS time from GPS
WARNING: [gps] could not get GPS time from GPS
WARNING: [gps] could not get GPS time from GPS
WARNING: [gps] could not get GPS time from GPS
WARNING: [gps] could not get GPS time from GPS
WARNING: [gps] could not get GPS time from GPS
WARNING: [gps] could not get GPS time from GPS
WARNING: [gps] could not get GPS time from GPS
WARNING: [gps] could not get GPS time from GPS

##### 2020-04-11 14:34:35 GMT #####
### [UPSTREAM] ###
# RF packets received by concentrator: 0
# CRC_OK: 0.00%, CRC_FAIL: 0.00%, NO_CRC: 0.00%
# RF packets forwarded: 0 (0 bytes)
# PUSH_DATA datagrams sent: 0 (0 bytes)
# PUSH_DATA acknowledged: 0.00%
### [DOWNSTREAM] ###
# PULL_DATA sent: 2 (0.00% acknowledged)
# PULL_RESP(onse) datagrams received: 0 (0 bytes)
# RF packets sent to concentrator: 0 (0 bytes)
# TX errors: 0
# BEACON queued: 0
# BEACON sent so far: 0
# BEACON rejected: 0
### [JIT] ###
# SX1301 time (PPS): 2672776
src/jitqueue.c:448:jit_print_queue(): INFO: [jit] queue is empty
### [GPS] ###
# Invalid time reference (age: 1586615675 sec)
# no valid GPS coordinates available yet
##### END #####

INFO: End of GPS thread

INFO: End of upstream thread
WARNING: failed to close GPS successfully
INFO: concentrator stopped successfully
INFO: Exiting packet forwarder program

and here is the log of util_pkt_logger:

loragw_pkt_logger: INFO: found global configuration file global_conf.json, trying to parse it
loragw_pkt_logger: INFO: global_conf.json does contain a JSON object named SX1301_conf, parsing SX1301 parameters
loragw_pkt_logger: INFO: lorawan_public 1, clksrc 1
lgw_board_setconf:427: Note: board configuration; lorawan_public:1, clksrc:1
loragw_pkt_logger: INFO: radio 0 enabled (type SX1257), center frequency 923600000, RSSI offset -166.000000, tx enabled 1, tx_notch_freq 0
lgw_rxrf_setconf:476: WARNING: NOT A VALID TX NOTCH FILTER FREQUENCY [126000..250000]Hz
lgw_rxrf_setconf:488: Note: rf_chain 0 configuration; en:1 freq:923600000 rssi_offset:-166.000000 radio_type:2 tx_enable:1 tx_notch_freq:0
loragw_pkt_logger: INFO: radio 1 enabled (type SX1257), center frequency 924600000, RSSI offset -166.000000, tx enabled 0, tx_notch_freq 0
lgw_rxrf_setconf:488: Note: rf_chain 1 configuration; en:1 freq:924600000 rssi_offset:-166.000000 radio_type:2 tx_enable:0 tx_notch_freq:0
loragw_pkt_logger: INFO: LoRa multi-SF channel 0 enabled, radio 0 selected, IF -400000 Hz, 125 kHz bandwidth, SF 7 to 12
lgw_rxif_setconf:607: Note: LoRa 'multi' if_chain 0 configuration; en:1 freq:-400000 SF_mask:0x7e
loragw_pkt_logger: INFO: LoRa multi-SF channel 1 enabled, radio 0 selected, IF -200000 Hz, 125 kHz bandwidth, SF 7 to 12
lgw_rxif_setconf:607: Note: LoRa 'multi' if_chain 1 configuration; en:1 freq:-200000 SF_mask:0x7e
loragw_pkt_logger: INFO: LoRa multi-SF channel 2 enabled, radio 0 selected, IF 0 Hz, 125 kHz bandwidth, SF 7 to 12
lgw_rxif_setconf:607: Note: LoRa 'multi' if_chain 2 configuration; en:1 freq:0 SF_mask:0x7e
loragw_pkt_logger: INFO: LoRa multi-SF channel 3 enabled, radio 0 selected, IF 200000 Hz, 125 kHz bandwidth, SF 7 to 12
lgw_rxif_setconf:607: Note: LoRa 'multi' if_chain 3 configuration; en:1 freq:200000 SF_mask:0x7e
loragw_pkt_logger: INFO: LoRa multi-SF channel 4 enabled, radio 0 selected, IF 400000 Hz, 125 kHz bandwidth, SF 7 to 12
lgw_rxif_setconf:607: Note: LoRa 'multi' if_chain 4 configuration; en:1 freq:400000 SF_mask:0x7e
loragw_pkt_logger: INFO: LoRa multi-SF channel 5 enabled, radio 1 selected, IF -400000 Hz, 125 kHz bandwidth, SF 7 to 12
lgw_rxif_setconf:607: Note: LoRa 'multi' if_chain 5 configuration; en:1 freq:-400000 SF_mask:0x7e
loragw_pkt_logger: INFO: LoRa multi-SF channel 6 enabled, radio 1 selected, IF -200000 Hz, 125 kHz bandwidth, SF 7 to 12
lgw_rxif_setconf:607: Note: LoRa 'multi' if_chain 6 configuration; en:1 freq:-200000 SF_mask:0x7e
loragw_pkt_logger: INFO: LoRa multi-SF channel 7 enabled, radio 1 selected, IF 0 Hz, 125 kHz bandwidth, SF 7 to 12
lgw_rxif_setconf:607: Note: LoRa 'multi' if_chain 7 configuration; en:1 freq:0 SF_mask:0x7e
loragw_pkt_logger: INFO: LoRa standard channel enabled, radio 1 selected, IF -100000 Hz, 250000 Hz bandwidth, SF 7
lgw_rxif_setconf:581: Note: LoRa 'std' if_chain 8 configuration; en:1 freq:-100000 bw:2 dr:2
loragw_pkt_logger: INFO: FSK channel enabled, radio 1 selected, IF 200000 Hz, 125000 Hz bandwidth, 50000 bps datarate
lgw_rxif_setconf:637: Note: FSK if_chain 9 configuration; en:1 freq:200000 bw:3 dr:50000 (50000 real dr) sync:0xC194C1
loragw_pkt_logger: INFO: global_conf.json does contain a JSON object named gateway_conf, parsing gateway parameters
loragw_pkt_logger: INFO: gateway MAC address is configured to 0000000000000000
loragw_pkt_logger: INFO: found local configuration file local_conf.json, trying to parse it
loragw_pkt_logger: INFO: local_conf.json does not contain a JSON object named SX1301_conf
loragw_pkt_logger: INFO: local_conf.json does contain a JSON object named gateway_conf, parsing gateway parameters
loragw_pkt_logger: INFO: gateway MAC address is configured to AA555A0000000101
lgw_start:823: Note: calibration started (time: 2300 ms)
lgw_start:844: Note: calibration finished (status = 183)
WARNING: problem in calibration of radio A for image rejection
Info: Initialising AGC firmware...
Info: putting back original RADIO_SELECT value
loragw_pkt_logger: INFO: concentrator started, packet can now be received
loragw_pkt_logger: INFO: Now writing to log file pktlog_AA555A0000000101_20200411T142341Z.csv
loragw_pkt_logger: INFO: concentrator stopped successfully
loragw_pkt_logger: INFO: log file pktlog_AA555A0000000101_20200411T142341Z.csv closed, 0 packet(s) recorded
loragw_pkt_logger: INFO: Exiting packet logger program

…and a side-question: the other gateway I have, RAK831, is labeled AU915. Will it work with the AS923 configuration?

PS. I did however succeed in having my RAK2245 connect to a remote ChirpStack network server and application server. Hope this info may help.

I’m learning LoRa and LoRaWAN, and any pointers is highly appreciated!

Chao

After some further experiments, I guess I’ve identified some of the problem: it was due to some message-format mismatch between the sender (e.g., Reyax RYLR896) and the receiver (e.g., RAK2245).

The Reyax RYLR896 LoRa module has attached an additional layer of encoding, and it is unclear how that translates to a LoRaWAN uplink message format. Previously, I was able to use another end device (Dragino LoRa GPS HAT) to receive messages from the module, because both operated over pure LoRa, not LoRaWAN. And none of these devices can talk to RAK2245 over pure LoRa message.

After I updated my Dragino device to adopt the LoRaWAN message format, my RAK2245 started receiving 100% uplink messages :slight_smile:

In hindsight, I guess the SX1301 chip powering RAK2245 just cannot tell my ill-formatted LoRa messages, and it ended up chopping message arrivals into some wrong segments. That might also explain why sometimes the gateway would complain CRC errors of some ghost messages sent at other frequencies (which I didn’t send).

Chao

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This is probably a case of mismatched configuration, not misformatting. It is certainly NOT a hardware incompatibility.

The most likely suspect is that you are using incompatible packet preambles between the sender and gateway. There is a choice there, which in some places has been documented as “public vs private” and in others as “LoRaWAN vs not” - so particularly with a source that is not LoRaWAN and a gateway configuration that is for public LoRaWAN, there’s a high likelihood of a preamble mismatch.

It turns out that the pre-amble detector “leaks” so even with a mismatch you will get a fraction of your packets through - but still end up missing a lot of them, which seems to be the difficulty you reported.

Thank you, @cstratton! This is very valuable information. I’ll check with Reyax to see how to properly configure the preamble for that chip.

Is there a way to prevent the preamble detector from leaking?

Thanks,
Chao

That incidentally indicates that your packet forwarder gave up because it was not in contact with a network server.

According to your logs you have the gateway set to the public/lorawan pre-amble, this would be in one of the two gateway config json files.

Leakage of the preamble detector isn’t really an issue, think of it like a spam filter - packets that aren’t for your network still get reported out by the baseband chip now and gthen but they’re dropped by the server when the device IDs and or keys don’t match, dropping them at the preamble detection stage just ideally leaves hardware decoders free to chase valid possibilities, and saves sending them over the internet backhaul, neither of which is a very big issue if it happens accidentally now and then. Making the detector “pickier” could make it miss valid packets.

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