This repository provides an idea how to add (TDOA) fine timestamp support on LoRa Basics™ Station v2.0.6 version. Repository presents perhaps the world's first (public) implementation of the Basic Station with a Fine timestamp ;).
Repository of the original LoRa Basics™ Station implementation can be found here.
Documentation about the Concentrator Corecell desing found here.
Another very good repository on this topic is xoseperez/basicstation.
GLS Basic Station enables The Fine timestamp functionality if consentrator hardware basis on the Semtech SX1303 or SX1302 chip and Semtech Corecell Desing. Concept has been tested on a Semtech SX1303 reference design board with an external EBYTE GN02 GPS module generating PPS pulse.
Testing has been done on ChirpStack v4 LoRaWAN® Network Server + GLS ChirpStack Gateway Bridge + GLS Basic Station back end combination. GLS ChirpStack Gateway Bridge is modified version of the original Chirpstack gateway bridge and it enables the fineTimeSinceGpsEpoch field in uplink event JSON messages with nanosecond precision as follows:
...
"rxInfo": [
{
"gatewayId": "0016c001ffxxxxxx",
"uplinkId": 3232276575,
"time": "2022-12-26T12:01:47.709920+00:00",
"timeSinceGpsEpoch": "1356091325.709920s",
"fineTimeSinceGpsEpoch": "1356091325.263021396s",
"rssi": -45,
"snr": 14.25,
"location": {
"latitude": 62.1979847889177,
"longitude": 21.123254060745244
},
"context": "AAAAAAAAAAAAMgABVWHvOA==",
"metadata": {
"region_common_name": "EU868",
"region_name": "eu868"
}
},
...
This repository not cover details of the GLS ChirpStack test environment configuration. But anyway, the Chirpstack gateway bridge needs to some code changes to work together with the GLS Basic Station implemetation. See GLS ChirpStack Gateway Bridge repository.
-
LoRa Basics™ station documentation and compilation instructions.
$ git clone https://github.com/LouneCode/gls-basicstation.git
Go gls-basicstation folder after cloning the repository. Give following commands on command line.
$ cd gls-basicstation
$ sudo docker build --network host --build-arg VARIANT=std --build-arg ARCH=amd64 . -t gls-basicstation:2.0.6.1.Gnu
Use the aarch64-alpine-linux-musl arm64 architecture compilling a Docker image of the GLS Basic station for Raspberry Pi 4, CM4.
$ cd gls-basicstation
$ sudo docker build --network host --build-arg VARIANT=std --build-arg ARCH=x86_64-alpine-linux-musl . -t gls-basicstation:2.0.6.1.Alpine -f Dockerfile-alpine
Check images of the container after compilation phase.
$ docker images
REPOSITORY TAG IMAGE ID CREATED SIZE
gls-basicstation 2.0.6.1.Alpine 80976a8432fd About a minute ago 15.8MB
gls-basicstation 2.0.6.1.Gnu b5bf738aa277 5 minutes ago 112MB
ubuntu 22.04 58db3edaf2be 2 weeks ago 77.8MB
...
Notice the size of the Alpine version (15.8MB).
Configure and run gls-basicstation image in Docker.
$ sudo docker run -d --name=gls-basicstation --device=/dev/ttyACM0:/dev/ttyACM0 \
--restart=unless-stopped --network=host -e TC_URI="ws://192.168.1.100:3001" \
-e MODEL="SX1303" -e INTERFACE="USB" -e DESIGN="CORECELL" \
-e DEVICE="/dev/ttyACM1" -e GATEWAY_EUI="E45F01FFFE1DDCAA" \
-e TC_KEY="eyJ0eXAiOiJKV1QiLCJhbGciOiJIUzI1fhifq-CeXj1GMMZc......." \
gls-basicstation:2.0.6.1.Alpine
List of environment variables (-e VARIABLE) of Docker run command
Only MODEL and TC_KEY are mandatory.
| Variable Name | Value | Description | Default |
|---|---|---|---|
MODEL |
STRING |
Concentrator model (see Define your MODEL section below) |
SX1303 |
INTERFACE |
SPI or USB |
Concentrator interface | SPI |
DESIGN |
CORECELL |
Concentrator design version | A fair guess will be done based on MODEL and INTERFACE |
DEVICE |
STRING |
Where the concentrator is connected to | /dev/spidev0.0 for SPI, /dev/ttyACM0 for USB |
USE_LIBGPIOD |
INT |
Use libgpiod (1) instead of default sysfs (0) to manage the GPIOs. The former is the recommended but not yet supported on all platforms. |
0 |
GW_RESET_GPIO |
INT |
GPIO number that resets (Broadcom pin number, if not defined it's calculated based on the GW_RESET_PIN) |
17 |
GW_POWER_EN_GPIO |
INT |
GPIO number that enables power (by pulling HIGH) to the concentrator (Broadcom pin number). 0 means no required. | 0 |
GW_POWER_EN_LOGIC |
INT |
If GW_POWER_EN_GPIO is not 0, the corresponding GPIO will be set to this value |
1 |
GATEWAY_EUI_NIC |
STRING |
Interface to use when generating the EUI | eth0 |
GATEWAY_EUI |
STRING |
Gateway EUI to use | Autogenerated from GATEWAY_EUI_NIC if defined, otherwise in order |
USE_CUPS |
0 or 1 | Set to 1 to force CUPS even without a CUPS_KEY variable or cups.key file | 0 |
CUPS_URI |
STRING |
CUPS Server to connect to | Automatically created based on SERVER |
CUPS_TRUST |
STRING |
Certificate for the CUPS server | Precached certificate |
CUPS_KEY |
STRING |
Unique gateway key used to connect to the CUPS server | Paste API key from your provider |
TC_URI |
STRING |
LoRaWAN Network Server to connect to | Automatically created based on SERVER |
TC_KEY |
STRING |
Unique gateway key used to connect to the LNS | Paste API key from your LNS |
At least
MODELandTC_KEYmust be defined.
When using CUPS (setting
USE_CUPSto 1 or defining theCUPS_KEYvariable), LNS configuration is retrieved from the CUPS server, so you don't have to set theTC_*variables.
The model is defined depending on the version of the LoRa concentrator chip: SX1302 or SX1303 . You can also use the concentrator module name or even the gateway model (for RAKwireless gateways). List of possible valid values:
- Semtech chip model: SX1302, SX1303
- Concentrator modules: RAK2287, RAK5146, RAK831, WM1302
- RAK WisGate Development gateways: RAK7248, RAK7248C, RAK7271, RAK7371
$ docker ps
CONTAINER ID IMAGE COMMAND CREATED STATUS PORTS NAMES
9599e6bfaffc gls-basicstation:2.0.6.1 "/app/start.sh" 7 minutes ago Up 7 minutes gls-basicstation
$ docker logs -f gls-basicstation
------------------------------------------------------------------
Protocol
------------------------------------------------------------------
Mode: DYNAMIC
Protocol: LNS
LNS Server: ws://192.168.1.100:3001
Gateway EUI: E45F01FFFE1DDCAA
------------------------------------------------------------------
Radio
------------------------------------------------------------------
Model: SX1303
Concentrator: SX1303
Design: CORECELL
Radio Device: /dev/ttyACM1
Interface: USB
Reset GPIO: 0
Enable GPIO: 0
------------------------------------------------------------------
2022-12-26 14:49:11.461 [SYS:INFO] Logging : stderr (maxsize=10000000, rotate=3)
2022-12-26 14:49:11.461 [SYS:INFO] Station Ver : 2.0.6(corecell/std) 2022-12-25 13:02:48
2022-12-26 14:49:11.461 [SYS:INFO] Package Ver : (null)
2022-12-26 14:49:11.461 [SYS:INFO] mbedTLS Ver : 2.28.0
2022-12-26 14:49:11.461 [SYS:INFO] proto EUI : e45f:1ff:fe1d:dc57 (station.conf)
2022-12-26 14:49:11.461 [SYS:INFO] prefix EUI : ::1 (builtin)
2022-12-26 14:49:11.461 [SYS:INFO] Station EUI : e45f:1ff:fe1d:dc57
2022-12-26 14:49:11.461 [SYS:INFO] Station home: ./ (builtin)
2022-12-26 14:49:11.461 [SYS:INFO] Station temp: /var/tmp/ (builtin)
2022-12-26 14:49:11.461 [SYS:WARN] Station in NO-CUPS mode
2022-12-26 14:49:11.662 [TCE:INFO] Starting TC engine
2022-12-26 14:49:11.662 [TCE:INFO] Connecting to INFOS: ws://192.168.1.176:3001
2022-12-26 14:49:11.690 [TCE:INFO] Infos: e45f:01ff:fe1d:dc57 e45f:01ff:fe1d:dc57 ws://192.168.1.100:3001/gateway/e45f01fffe1ddc57
2022-12-26 14:49:11.690 [AIO:DEBU] [3] ws_close reason=1000
2022-12-26 14:49:11.690 [AIO:DEBU] [3] Connection closed unexpectedly
2022-12-26 14:49:11.690 [AIO:DEBU] [3] WS connection shutdown...
2022-12-26 14:49:11.691 [TCE:VERB] Connecting to MUXS...
2022-12-26 14:49:11.707 [TCE:VERB] Connected to MUXS.
...
2022-12-26 14:49:11.723 [RAL:INFO] Fine timestamp enabled.
...
2022-12-26 14:49:11.731 [RAL:INFO] Station device: usb:/dev/ttyACM1 (PPS capture enabled)
2022-12-26 14:49:11.731 [HAL:INFO] [lgw_com_open:88] Opening USB communication interface
2022-12-26 14:49:11.731 [HAL:INFO] [lgw_usb_open:162] INFO: Configuring TTY
2022-12-26 14:49:11.731 [HAL:INFO] [lgw_usb_open:171] INFO: Flushing TTY
2022-12-26 14:49:11.731 [HAL:INFO] [lgw_usb_open:180] INFO: Setting TTY in blocking mode
2022-12-26 14:49:11.731 [HAL:INFO] [lgw_usb_open:195] INFO: Connect to MCU
2022-12-26 14:49:11.731 [HAL:INFO] [lgw_usb_open:203] INFO: Concentrator MCU version is V01.00.00
2022-12-26 14:49:11.731 [HAL:INFO] [lgw_usb_open:210] INFO: MCU status: sys_time:237473297 temperature:26.8oC
2022-12-26 14:49:11.733 [HAL:INFO] [lgw_connect:1192] chip version is 0x12 (v1.2)
2022-12-26 14:49:13.978 [HAL:INFO] [timestamp_counter_mode:435] using precision timestamp (max_ts_metrics:32 nb_symbols:0)
2022-12-26 14:49:14.225 [RAL:INFO] Concentrator started (2s494ms)
...
Run the make command in basicstation repository.
$ git clone https://github.com/lorabasics/basicstation basicstation
$ git clone https://github.com/LouneCode/gls-basicstation.git gls-basicstation
$ cd basicstation
$ git checkout v2.0.6
$ git apply ../gls-basicstation/builder/v2.0.6.patch
$ git apply ../gls-basicstation/builder/GLS_v2.0.6.1.patch
$ make arch=amd64 platform=corecell variant=std
Compiled files should found in a build-corecell-std folder. Detailed compilling instructions will be found in original Basic Station repository.
Add following Configuration files in basicstation folder before run binary. Set "pps" property to true in "SX1302_conf" section to enable the Fine timestamping functionality. All the following configuration files are examples only and should be reviewed and modified according to the Basic Station configuration used.
- station.conf
{
"SX1302_conf": {
"device": "usb:/dev/ttyACM0",
"lorawan_public": true,
"clksrc": 0,
"full_duplex": false,
"pps": true,
"radio_0": {
"type": "SX1250",
"rssi_offset": -215.4,
"rssi_tcomp": {"coeff_a": 0, "coeff_b": 0, "coeff_c": 20.41, "coeff_d": 2162.56, "coeff_e": 0},
"tx_enable": true,
"antenna_gain": 0,
"tx_gain_lut":[
{"rf_power": 12, "pa_gain": 0, "pwr_idx": 15},
{"rf_power": 13, "pa_gain": 0, "pwr_idx": 16},
{"rf_power": 14, "pa_gain": 0, "pwr_idx": 17},
{"rf_power": 15, "pa_gain": 0, "pwr_idx": 19},
{"rf_power": 16, "pa_gain": 0, "pwr_idx": 20},
{"rf_power": 17, "pa_gain": 0, "pwr_idx": 22},
{"rf_power": 18, "pa_gain": 1, "pwr_idx": 1},
{"rf_power": 19, "pa_gain": 1, "pwr_idx": 2},
{"rf_power": 20, "pa_gain": 1, "pwr_idx": 3},
{"rf_power": 21, "pa_gain": 1, "pwr_idx": 4},
{"rf_power": 22, "pa_gain": 1, "pwr_idx": 5},
{"rf_power": 23, "pa_gain": 1, "pwr_idx": 6},
{"rf_power": 24, "pa_gain": 1, "pwr_idx": 7},
{"rf_power": 25, "pa_gain": 1, "pwr_idx": 9},
{"rf_power": 26, "pa_gain": 1, "pwr_idx": 11},
{"rf_power": 27, "pa_gain": 1, "pwr_idx": 14}
]
},
"radio_1": {
"type": "SX1250",
"rssi_offset": -215.4,
"rssi_tcomp": {"coeff_a": 0, "coeff_b": 0, "coeff_c": 20.41, "coeff_d": 2162.56, "coeff_e": 0},
"tx_enable": false
}
},
"station_conf": {
"routerid": "0016F001FF1F0FEE",
"RADIO_INIT_WAIT": "5s",
"RX_POLL_INTV": "10ms",
"TC_TIMEOUT": "360s",
"log_file": "stderr",
"log_level": "XDEBUG",
"log_size": 10000000,
"log_rotate": 3
}
}
- tc.key
Authorization: Bearer eyJ0eXAiOiJKV1QiLCJhbGciOiJIUzI1NiJ9.eyJhdWQiOiJjaGlycHN0YWNrIiwiaXNzIjoiY2hpcnBzdGFjayIsInN1YiI6Ijk0Mjg4NDA3LTFjYzUtNGViMC...
- tc.uri
ws://192.168.1.100:3001
sudo ./build-corecell-std/bin/station
The Station binary accepts the following command-line options:
Usage: station [OPTION...]
-d, --daemon First check if another process is still alive. If
so do nothing and exit. Otherwise fork a worker
process to operate the radios and network
protocols. If the subprocess died respawn it with
an appropriate back off.
-f, --force If a station process is already running, kill it
before continuing with requested operation mode.
-h, --home=DIR Home directory for configuration files. Default is
the current working directory. Overrides
environment STATION_DIR.
-i, --radio-init=cmd Program/script to run before reinitializing radio
hardware. By default nothing is being executed.
Overrides environment STATION_RADIOINIT.
-k, --kill Kill a currently running station process.
-l, --log-level=LVL|0..7 Set a log level LVL=#loglvls# or use a numeric
value. Overrides environment STATION_LOGLEVEL.
-L, --log-file=FILE[,SIZE[,ROT]]
Write log entries to FILE. If FILE is '-' then
write to stderr. Optionally followed by a max file
SIZE and a number of rotation files. If ROT is 0
then keep only FILE. If ROT is 1 then keep one
more old log file around. Overrides environment
STATION_LOGFILE.
-N, --no-tc Do not connect to a LNS. Only run CUPS
functionality.
-p, --params Print current parameter settings.
-t, --temp=DIR Temp directory for frequently written files.
Default is /tmp. Overrides environment
STATION_TEMPDIR.
-x, --eui-prefix=id6 Turn MAC address into EUI by adding this prefix.
If the argument has value ff:fe00:0 then the EUI
is formed by inserting FFFE in the middle. If
absent use MAC or routerid as is. Overrides
environment STATION_EUIPREFIX.
-?, --help Give this help list
--usage Give a short usage message
-v, --version Print station version.
Mandatory or optional arguments to long options are also mandatory or optional
for any corresponding short options.
---
2022-12-19 17:17:46.690 [RAL:INFO] Fine timestamp enabled.
---
2022-12-19 17:20:14.782 [HAL:XDEB] [rx_buffer_pop:275] Packet checksum OK (0x79)
2022-12-19 17:20:14.782 [HAL:XDEB] [rx_buffer_pop:311] -----------------
2022-12-19 17:20:14.782 [HAL:XDEB] [rx_buffer_pop:312] modem: 9
2022-12-19 17:20:14.782 [HAL:XDEB] [rx_buffer_pop:313] chan: 5
2022-12-19 17:20:14.782 [HAL:XDEB] [rx_buffer_pop:314] size: 37
2022-12-19 17:20:14.782 [HAL:XDEB] [rx_buffer_pop:315] crc_en: 1
2022-12-19 17:20:14.782 [HAL:XDEB] [rx_buffer_pop:316] crc_err: 0
2022-12-19 17:20:14.782 [HAL:XDEB] [rx_buffer_pop:317] sync_err: 0
2022-12-19 17:20:14.782 [HAL:XDEB] [rx_buffer_pop:318] hdr_err: 0
---
2022-12-19 17:20:14.782 [HAL:XDEB] [rx_buffer_pop:319] timing_set: 1
---
2022-12-19 17:20:14.782 [HAL:XDEB] [rx_buffer_pop:320] codr: 1
2022-12-19 17:20:14.782 [HAL:XDEB] [rx_buffer_pop:321] datr: 7
2022-12-19 17:20:14.782 [HAL:XDEB] [rx_buffer_pop:322] num_ts: 30
2022-12-19 17:20:14.782 [HAL:XDEB] [rx_buffer_pop:324] ts_avg:
---
2022-12-19 17:20:14.783 [HAL:XDEB] [sx1302_parse:1959] Note: LoRa packet (modem 9 chan 5)
2022-12-19 17:20:14.783 [HAL:XDEB] [sx1302_parse:1981] Payload CRC check OK (0xCC3C)
2022-12-19 17:20:14.783 [HAL:XDEB] [precision_timestamp_correction:253] FTIME ON : timestamp correction 61421
2022-12-19 17:20:14.785 [HAL:XDEB] [precise_timestamp_calculate:587] ==> timestamp_pps => 362418142
2022-12-19 17:20:14.785 [HAL:XDEB] [precise_timestamp_calculate:605] timestamp_cnt : 384430325
2022-12-19 17:20:14.785 [HAL:XDEB] [precise_timestamp_calculate:606] timestamp_pps : 362418142
2022-12-19 17:20:14.785 [HAL:XDEB] [precise_timestamp_calculate:607] diff_pps : 22012183
2022-12-19 17:20:14.785 [HAL:XDEB] [precise_timestamp_calculate:611] pkt_ftime = 22012180.733333
2022-12-19 17:20:14.785 [HAL:XDEB] [precise_timestamp_calculate:628] ==> ftime = 687880518 ns since last PPS (687880518.939069867134094)
2022-12-19 17:20:14.785 [HAL:XDEB] [sx1302_rssi_get_temperature_offset:2283] INFO: RSSI temperature compensation:
2022-12-19 17:20:14.785 [HAL:XDEB] [sx1302_rssi_get_temperature_offset:2284] coeff_a: 0.000
2022-12-19 17:20:14.785 [HAL:XDEB] [sx1302_rssi_get_temperature_offset:2285] coeff_b: 0.000
2022-12-19 17:20:14.785 [HAL:XDEB] [sx1302_rssi_get_temperature_offset:2286] coeff_c: 20.410
2022-12-19 17:20:14.785 [HAL:XDEB] [sx1302_rssi_get_temperature_offset:2287] coeff_d: 2162.560
2022-12-19 17:20:14.785 [HAL:XDEB] [sx1302_rssi_get_temperature_offset:2288] coeff_e: 0.000
2022-12-19 17:20:14.785 [HAL:XDEB] [lgw_receive:1320] INFO: RSSI temperature offset applied: 1.124 dB (current temperature 27.1 C)
2022-12-19 17:20:14.785 [HAL:XDEB] [lgw_receive:1323] INFO: nb pkt found:1 left:1
2022-12-19 17:20:14.785 [HAL:XDEB] [merge_packets:340] <----- Searching for DUPLICATEs ------
2022-12-19 17:20:14.785 [HAL:XDEB] [merge_packets:343] 0: tmst=146305065 SF=7 CRC_status=16 freq=868100000 chan=5
---
2022-12-19 17:20:14.785 [HAL:XDEB] [merge_packets:345] ftime=687880518
---
2022-12-19 17:20:14.785 [HAL:XDEB] [merge_packets:425] 0 elements swapped during sorting...
2022-12-19 17:20:14.785 [HAL:XDEB] [merge_packets:430] --
2022-12-19 17:20:14.785 [HAL:XDEB] [merge_packets:433] 0: tmst=146305065 SF=7 CRC_status=16 freq=868100000 chan=5
2022-12-19 17:20:14.785 [HAL:XDEB] [merge_packets:435] ftime=687880518
2022-12-19 17:20:14.785 [HAL:XDEB] [merge_packets:441] ------------------------------------>
---
2022-12-19 17:20:14.792 [RAL:XDEB] [CRC OK] 868.100MHz 13.75/-45.3 SF7/BW125 (mod=16/dr=7/bw=4) xtick=08b8702a (146305066) 37 bytes: 401032B50080100502EF892139DAF173F4B91023FC1856702277375E797CF865FF30CFB69B
---
2022-12-19 17:20:14.792 [S2E:DEBU] Copy the fine timestamp [687880518] of the previous mirror frame before drop it.
---
2022-12-19 17:20:14.792 [S2E:DEBU] Dropped mirror frame freq=868.1MHz snr= 11.5 rssi=-45 (vs. freq=868.1MHz snr= 13.8 rssi=-45) - DR5 mic=-1682518224 (37 bytes)
2022-12-19 17:20:14.797 [S2E:VERB] RX 868.1MHz DR5 SF7/BW125 snr=13.8 rssi=-45 xtime=0xB8000008B8702A fts=687880518 - updf mhdr=40 DevAddr=00B53210 FCtrl=80 FCnt=1296 FOpts=[] 02EF8921..65FF mic=-1682518224 (37 bytes)
2022-12-19 17:20:14.797 [AIO:XDEB] [3|WS] > {"msgtype":"updf","MHdr":64,"DevAddr":11874832,"FCtrl":128,"FCnt":1296,"FOpts":"","FPort":2,"FRMPayload":"EF892139DAF173F4B91023FC1856702277375E797CF865FF","MIC":-1682518224,"RefTime":0.000000,"DR":5,"Freq":868100000,"upinfo":{"rctx":0,"xtime":51791395861065770,"gpstime":1355505632761772,"fts":687880518,"rssi":-45,"snr":13.75,"rxtime":1671470414.687880516}}
---
Fine timestamp in the web socket message ---> "fts":687880518
2022-12-19 17:20:14.797 [AIO:XDEB] [3|WS] > {"msgtype":"updf","MHdr":64, --- "fts":687880518 --- ,"rssi":-45,"snr":13.75,"rxtime":1671470414.687880516}}
- This is an adaptation of the Semtech Basics Station repository. See the documentation.
- Docker image compilation scripts bases on excellent work done by xoseperez/basicstation
The contents of this repository (not of those repositories linked or used by this one) are under BSD 3-Clause License.
Copyright (c) 2023 LouneCode - Only husky in the village postia.lounelle@live.com All rights reserved.
Redistribution and use in source and binary forms, with or without modification, are permitted provided that the following conditions are met:
- Redistributions of source code must retain the above copyright notice, this list of conditions and the following disclaimer.
- Redistributions in binary form must reproduce the above copyright notice, this list of conditions and the following disclaimer in the documentation and/or other materials provided with the distribution.
- Neither the name of this project nor the names of its contributors may be used to endorse or promote products derived from this software without specific prior written permission.
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