Basic Station Protocol problem for RAK7243 with LTE

LPWAN Developer Gateways / Concentrators
1

Hi, everyone. Recently, We are working on the basic station protocol with RAK7243 DIY gw. The destination LNS is ttn stack v3. Other problems have already fixed except one. Here, I addresses the logs:
2020-08-16 03:54:05.427 [TCE:VERB] Connecting to MUXS…
2020-08-16 03:54:05.721 [TCE:VERB] Connected to MUXS.
2020-08-16 03:54:05.725 [RAL:WARN] Ignoring unsupported/unknown field: antenna_gain
2020-08-16 03:54:05.725 [RAL:INFO] Lora gateway library version: Version: 5.0.1;
2020-08-16 03:54:05.727 [RAL:VERB] Connecting to device: /dev/spidev0.0
2020-08-16 03:54:05.727 [RAL:DEBU] SX130x txlut table (0 entries)
2020-08-16 03:54:05.727 [RAL:VERB] SX1301 rxrfchain 0: enable=1 freq=923.6MHz rssi_offset=-166.000000 type=2 tx_enable=1 tx_notch_freq=0
2020-08-16 03:54:05.727 [RAL:VERB] SX1301 rxrfchain 1: enable=1 freq=924.6MHz rssi_offset=-166.000000 type=2 tx_enable=0 tx_notch_freq=0
2020-08-16 03:54:05.727 [RAL:VERB] SX1301 ifchain 0: enable=1 rf_chain=0 freq=-400000 bandwidth=0 datarate=0 sync_word=0/0
2020-08-16 03:54:05.727 [RAL:VERB] SX1301 ifchain 1: enable=1 rf_chain=0 freq=-200000 bandwidth=0 datarate=0 sync_word=0/0
2020-08-16 03:54:05.727 [RAL:VERB] SX1301 ifchain 2: enable=1 rf_chain=0 freq=0 bandwidth=0 datarate=0 sync_word=0/0
2020-08-16 03:54:05.727 [RAL:VERB] SX1301 ifchain 3: enable=1 rf_chain=0 freq=200000 bandwidth=0 datarate=0 sync_word=0/0
2020-08-16 03:54:05.727 [RAL:VERB] SX1301 ifchain 4: enable=1 rf_chain=0 freq=400000 bandwidth=0 datarate=0 sync_word=0/0
2020-08-16 03:54:05.727 [RAL:VERB] SX1301 ifchain 5: enable=1 rf_chain=1 freq=-400000 bandwidth=0 datarate=0 sync_word=0/0
2020-08-16 03:54:05.727 [RAL:VERB] SX1301 ifchain 6: enable=1 rf_chain=1 freq=-200000 bandwidth=0 datarate=0 sync_word=0/0
2020-08-16 03:54:05.727 [RAL:VERB] SX1301 ifchain 7: enable=1 rf_chain=1 freq=0 bandwidth=0 datarate=0 sync_word=0/0
2020-08-16 03:54:05.727 [RAL:VERB] SX1301 ifchain 8: enable=1 rf_chain=1 freq=-100000 bandwidth=2 datarate=2 sync_word=0/0
2020-08-16 03:54:05.727 [RAL:VERB] SX1301 ifchain 9: enable=1 rf_chain=1 freq=200000 bandwidth=3 datarate=50000 sync_word=0/0
2020-08-16 03:54:05.727 [RAL:VERB] SX130x LBT not enabled
2020-08-16 03:54:05.727 [RAL:VERB] Station device: /dev/spidev0.0 (PPS capture disabled)
2020-08-16 03:54:08.889 [RAL:VERB] Concentrator started (3s161ms)
2020-08-16 03:54:08.889 [S2E:INFO] Configuring for region: AS923 – 923.2MHz…925.0MHz
2020-08-16 03:54:08.889 [S2E:VERB] DR0 SF12/BW125
2020-08-16 03:54:08.889 [S2E:VERB] DR1 SF11/BW125
2020-08-16 03:54:08.889 [S2E:VERB] DR2 SF10/BW125
2020-08-16 03:54:08.889 [S2E:VERB] DR3 SF9/BW125
2020-08-16 03:54:08.890 [S2E:VERB] DR4 SF8/BW125
2020-08-16 03:54:08.890 [S2E:VERB] DR5 SF7/BW125
2020-08-16 03:54:08.890 [S2E:VERB] DR6 SF7/BW250
2020-08-16 03:54:08.890 [S2E:VERB] DR7 FSK
2020-08-16 03:54:08.890 [S2E:VERB] DR8 FSK
2020-08-16 03:54:08.890 [S2E:VERB] DR9 FSK
2020-08-16 03:54:08.890 [S2E:VERB] DR10 FSK
2020-08-16 03:54:08.890 [S2E:VERB] DR11 FSK
2020-08-16 03:54:08.890 [S2E:VERB] DR12 FSK
2020-08-16 03:54:08.890 [S2E:VERB] DR13 FSK
2020-08-16 03:54:08.890 [S2E:VERB] DR14 FSK
2020-08-16 03:54:08.890 [S2E:VERB] DR15 FSK
2020-08-16 03:54:08.890 [S2E:VERB] TX power: 14.0 dBm EIRP
2020-08-16 03:54:08.890 [S2E:VERB] JoinEui list: 0 entries
2020-08-16 03:54:08.890 [S2E:VERB] NetID filter: FFFFFFFF-FFFFFFFF-FFFFFFFF-FFFFFFFF
2020-08-16 03:54:08.890 [S2E:VERB] Dev/test settings: nocca=1 nodc=1 nodwell=1
2020-08-16 03:54:50.894 [SYN:INFO] MCU/SX130X drift stats: min: +0.0ppm q50: -1.4ppm q80: +4.3ppm max: -5.2ppm - threshold q90: -4.8ppm
2020-08-16 03:54:50.894 [SYN:INFO] Mean MCU drift vs SX130X#0: -0.5ppm
2020-08-16 03:54:57.195 [SYN:ERRO] Repeated excessive clock drifts between MCU/SX130X#0 (3 retries): 1458302.9ppm (threshold 4.8ppm)
2020-08-16 03:55:00.345 [SYN:ERRO] Repeated excessive clock drifts between MCU/SX130X#0 (6 retries): 3302230.8ppm (threshold 4.8ppm)
2020-08-16 03:55:02.446 [SYN:INFO] Time sync qualities: min=63 q90=90 max=149 (previous q90=2147483647)
2020-08-16 03:55:03.496 [SYN:ERRO] Repeated excessive clock drifts between MCU/SX130X#0 (9 retries): 5146237.1ppm (threshold 100.0ppm)

I found that this maybe a time synchronization problem. However, in my indoor environment, GPS signal is alway weak. This means we could not use GPS to accurate the time.
So, any solutions to this issue?

Thx for your help. :smile:

2

Besides, the spi speed setting has already been configured.

3

How is that a "Basic Station Protocol problem?

Seems like you should either not use GPS, or move the gateway to a higher and potential outdoor location (would help with LoRa performance, too) or use an outdoor GPS antenna (though that might need a preamp).

Of course it could be something other than GPS, too. Does it receive any valid LoRa packets when valid ones are transmitted at a reasonable distance (say 50 meters)? If not, one may wonder if communication between the pi and the concentrator is really working correctly yet.