Intermittent reception of LoRa packets with MT gateway

[Antony Rix]

Hello,

I’ve set up a Conduit mLinux Ethernet gateway with a LoRa card to act as a LoRaWAN gateway and server, under EU operation. We also have a LoRaWAN gateway from Semtech, also with embedded server. Both are running alongside each other, along with 4 motes (2 from Semtech, 2 our own using different mbed LoRaWAN implementations).

The Semtech gateway is receiving close to 100% of packets.

The MT gateway is receiving perhaps 10% of packets, even though it should be capable of the same as the Semtech device.

We have followed the MT setup guidelines for EU mode. Our nodes are all set up using personalisation rather than OTA.

I would very much like to get the MT gateway working properly – can anyone help?

Details of our setup will follow.

Thanks

Antony

[Antony Rix]

Our setup:

root@mtcdt:~# cat /var/config/lora/lora-network-server.conf
{
“lora”: {
“netID”: “fef1f0”, /* netID for beacon packets */
“frequencyBand”: “868”, /* US=”915″, EU=”868″ */
“frequencySubBand”: 7, /* Sub-band for US operation, 1-8 */
“rx1DatarateOffset”: 0, /* Datarate offset for mote rx window 1 sent in join response (0-3) */
“rx2Datarate”: 12, /* Datarate for mote rx window 2 sent in join response (7-12) */
“maxTxPower”: 14, /* Max Tx power (dBm), -6 to 26 */
“frequencyEU”: 867500000 /* center freq for extra EU channels (Hz) */
},
“udp”: {
“appPortUp”: 1784, /* port for user-developed application use */
“appPortDown”: 1786 /* port for user-developed application use */
},
“addressRange”: {
“start”: “00:00:00:01”, /* address range used for mDots */
“end”: “FF:FF:FF:FE”
},
“network”: {
“public”: false, /* set to false for private LoRa network with mDots + Conduit */
“leasetime”: 1440, /* time until mDot join expires (minutes) */
“eui”: “FFFE000000000002”, /* not using MT name generation of EUI */
“key”: “0102030405060708090a0b0c0d0e0f00”
},
“log” : {
“console” : true,
“syslog” : false,
“level” : 30, /* error=10, warn=20, info=30, debug=50, trace=60, max=100 */
“path”: “/var/log/lora-network-server.log”
},
“mqtt”: {
“enabled”: true
}
}

Versions:
MT Conduit mLinux version
Linux version 3.12.27 (jenkins@frylock) (gcc version 4.8.2 (GCC) ) #1 Wed May 27 01:49:19 CDT 2015

lora-network-server_0.0.8-r0.0_arm926ejste.ipk
lora-packet-forwarder_1.4.1-r8.16_arm926ejste.ipk

4 nodes configured – 00b9bda5 and 000be716 are Semtech LoRaMote 868MHz devices, the others are mbed devices using the Semtech SX1276 mbed shield, running different off-the-shelf open source LoRa implementations. Note that one of these devices (running an LMIC implementation) has had zero packets received with the MT gateway.

root@mtcdt:~# nc -u localhost 6677
node list
Net Addr Dev EUI Joined Seq Num Up Down 1st 2nd Dropped RSSI min max avg SNR min max avg
00:0b:e7:16 00:00:00:00:00:0b:e7:16 2015-10-14T08:11:18Z 1486 308 0 0 0 0 -53 -22 -37 7.2 14.2 10.6
00:b9:bd:a5 00:00:00:00:00:b9:bd:a5 2015-10-14T08:11:18Z 1487 529 0 0 0 0 -31 -13 -17 4 14.2 11.5
01:0d:ec:af 00:00:00:00:20:00:02:a8 2015-10-14T09:07:00Z 195 35 0 0 0 0 -45 -25 -33 6.5 11 9.4
12:34:56:78 01:23:45:67:89:ab:cd:ef 2015-10-14T08:11:18Z 7 9 9 9 0 0 -32 -23 -25 7.8 10.8 9.6
78:56:34:12 01:23:45:67:89:ab:cd:ef 2015-10-14T08:11:18Z 0 0 0 0 0 0 0 0 0 0 0 0

Example MQTT output from MT:

mosquitto_sub -t lora/+/+ -v
lora/00:00:00:00:00:b9:bd:a5/up {“chan”:1,”cls”:0,”codr”:”4/5″,”data”:”ACflChX6Nf1KFLcABIwAEQ==”,”datr”:”SF9BW125″,”freq”:”868.3″,”lsnr”:”13.2″,”modu”:”LORA”,”rfch”:0,”rssi”:-27,”seqn”:1467,”size”:24,”timestamp”:”2015-10-14T09:47:40Z”,”tmst”:1625298916}

lora/00:00:00:00:00:b9:bd:a5/up {“chan”:5,”cls”:0,”codr”:”4/5″,”data”:”ACflCg/6LQVKFLgABI0AEQ==”,”datr”:”SF9BW125″,”freq”:”867.5″,”lsnr”:”10.2″,”modu”:”LORA”,”rfch”:1,”rssi”:-21,”seqn”:1469,”size”:24,”timestamp”:”2015-10-14T09:47:48Z”,”tmst”:1633981556}

lora/00:00:00:00:00:b9:bd:a5/up {“chan”:2,”cls”:0,”codr”:”4/5″,”data”:”ACflChX6LgRKFLgABI0AEQ==”,”datr”:”SF9BW125″,”freq”:”868.5″,”lsnr”:”9.2″,”modu”:”LORA”,”rfch”:0,”rssi”:-22,”seqn”:1470,”size”:24,”timestamp”:”2015-10-14T09:47:52Z”,”tmst”:1638005124}

lora/00:00:00:00:00:0b:e7:16/up {“chan”:4,”cls”:0,”codr”:”4/5″,”data”:”ACflCfz6LpdKFLUABI0AGQ==”,”datr”:”SF9BW125″,”freq”:”867.3″,”lsnr”:”12.2″,”modu”:”LORA”,”rfch”:1,”rssi”:-37,”seqn”:1474,”size”:24,”timestamp”:”2015-10-14T09:48:09Z”,”tmst”:1654222380}

lora/00:00:00:00:00:b9:bd:a5/up {“chan”:2,”cls”:0,”codr”:”4/5″,”data”:”ACflChv6M/9KFLYABI0AEQ==”,”datr”:”SF9BW125″,”freq”:”868.5″,”lsnr”:”8.2″,”modu”:”LORA”,”rfch”:0,”rssi”:-25,”seqn”:1474,”size”:24,”timestamp”:”2015-10-14T09:48:10Z”,”tmst”:1655203052}

lora/00:00:00:00:20:00:02:a8/up {“chan”:1,”cls”:0,”codr”:”4/5″,”data”:”mZmZmZmZmZk=”,”datr”:”SF7BW125″,”freq”:”868.3″,”lsnr”:”10″,”modu”:”LORA”,”rfch”:0,”rssi”:-29,”seqn”:192,”size”:12,”timestamp”:”2015-10-14T09:48:23Z”,”tmst”:1668382403}

lora/00:00:00:00:00:b9:bd:a5/up {“chan”:2,”cls”:0,”codr”:”4/5″,”data”:”ACflChX6KP1KFLYABI0AEQ==”,”datr”:”SF9BW125″,”freq”:”868.5″,”lsnr”:”8.8″,”modu”:”LORA”,”rfch”:0,”rssi”:-27,”seqn”:1478,”size”:24,”timestamp”:”2015-10-14T09:48:28Z”,”tmst”:1673741676}

lora/00:00:00:00:00:0b:e7:16/up {“chan”:6,”cls”:0,”codr”:”4/5″,”data”:”ACfkCfz6OJdKFLUABI0AGQ==”,”datr”:”SF9BW125″,”freq”:”867.7″,”lsnr”:”12″,”modu”:”LORA”,”rfch”:1,”rssi”:-37,”seqn”:1481,”size”:24,”timestamp”:”2015-10-14T09:48:40Z”,”tmst”:1685215580}

lora/00:00:00:00:00:b9:bd:a5/up {“chan”:5,”cls”:0,”codr”:”4/5″,”data”:”ACfmChX6MAFKFLgABI4AEQ==”,”datr”:”SF9BW125″,”freq”:”867.5″,”lsnr”:”9.2″,”modu”:”LORA”,”rfch”:1,”rssi”:-24,”seqn”:1481,”size”:24,”timestamp”:”2015-10-14T09:48:41Z”,”tmst”:1687001356}

lora/00:00:00:00:00:b9:bd:a5/up {“chan”:1,”cls”:0,”codr”:”4/5″,”data”:”ACfmChX6Lf5KFLsABI8AEQ==”,”datr”:”SF9BW125″,”freq”:”868.3″,”lsnr”:”11.5″,”modu”:”LORA”,”rfch”:0,”rssi”:-24,”seqn”:1483,”size”:24,”timestamp”:”2015-10-14T09:48:50Z”,”tmst”:1695753340}

lora/00:00:00:00:20:00:02:a8/up {“chan”:3,”cls”:0,”codr”:”4/5″,”data”:”mZmZmZmZmZk=”,”datr”:”SF7BW125″,”freq”:”867.1″,”lsnr”:”11″,”modu”:”LORA”,”rfch”:1,”rssi”:-29,”seqn”:195,”size”:12,”timestamp”:”2015-10-14T09:49:00Z”,”tmst”:1705170619}

lora/00:00:00:00:00:0b:e7:16/up {“chan”:5,”cls”:0,”codr”:”4/5″,”data”:”ACfmCfz6PZpKFLUABI0AGQ==”,”datr”:”SF9BW125″,”freq”:”867.5″,”lsnr”:”9″,”modu”:”LORA”,”rfch”:1,”rssi”:-41,”seqn”:1486,”size”:24,”timestamp”:”2015-10-14T09:49:02Z”,”tmst”:1707629972}

lora/00:00:00:00:00:b9:bd:a5/up {“chan”:2,”cls”:0,”codr”:”4/5″,”data”:”ACflChX6N/xKFLwABI8ADw==”,”datr”:”SF9BW125″,”freq”:”868.5″,”lsnr”:”8.5″,”modu”:”LORA”,”rfch”:0,”rssi”:-27,”seqn”:1486,”size”:24,”timestamp”:”2015-10-14T09:49:04Z”,”tmst”:1709271924}

lora/00:00:00:00:00:b9:bd:a5/up {“chan”:1,”cls”:0,”codr”:”4/5″,”data”:”ACfmChX6MQFKFLwABI8ADw==”,”datr”:”SF9BW125″,”freq”:”868.3″,”lsnr”:”13.2″,”modu”:”LORA”,”rfch”:0,”rssi”:-24,”seqn”:1487,”size”:24,”timestamp”:”2015-10-14T09:49:08Z”,”tmst”:1713406708}

lora/00:00:00:00:00:b9:bd:a5/up {“chan”:6,”cls”:0,”codr”:”4/5″,”data”:”ACfmChX6MANKFLwABI8ADw==”,”datr”:”SF9BW125″,”freq”:”867.7″,”lsnr”:”12″,”modu”:”LORA”,”rfch”:1,”rssi”:-27,”seqn”:1488,”size”:24,”timestamp”:”2015-10-14T09:49:12Z”,”tmst”:1717426852}

lora/00:00:00:00:00:0b:e7:16/up {“chan”:5,”cls”:0,”codr”:”4/5″,”data”:”ACfmCfz6NZpKFLUABI0AGQ==”,”datr”:”SF9BW125″,”freq”:”867.5″,”lsnr”:”9″,”modu”:”LORA”,”rfch”:1,”rssi”:-39,”seqn”:1490,”size”:24,”timestamp”:”2015-10-14T09:49:19Z”,”tmst”:1724219724}

lora/00:00:00:00:00:0b:e7:16/up {“chan”:2,”cls”:0,”codr”:”4/5″,”data”:”ACflCfz6NpVKFLUABI0AGQ==”,”datr”:”SF9BW125″,”freq”:”868.5″,”lsnr”:”9.2″,”modu”:”LORA”,”rfch”:0,”rssi”:-41,”seqn”:1491,”size”:24,”timestamp”:”2015-10-14T09:49:23Z”,”tmst”:1728138340}

lora/00:00:00:00:00:b9:bd:a5/up {“chan”:5,”cls”:0,”codr”:”4/5″,”data”:”ACfmChX6LAJKFLwABI4ADw==”,”datr”:”SF9BW125″,”freq”:”867.5″,”lsnr”:”9.2″,”modu”:”LORA”,”rfch”:1,”rssi”:-27,”seqn”:1493,”size”:24,”timestamp”:”2015-10-14T09:49:35Z”,”tmst”:1740267740}

lora/00:00:00:00:20:00:02:a8/up {“chan”:4,”cls”:0,”codr”:”4/5″,”data”:”mZmZmZmZmZk=”,”datr”:”SF7BW125″,”freq”:”867.3″,”lsnr”:”9.2″,”modu”:”LORA”,”rfch”:1,”rssi”:-25,”seqn”:198,”size”:12,”timestamp”:”2015-10-14T09:49:38Z”,”tmst”:1743904715}

lora/00:00:00:00:00:0b:e7:16/up {“chan”:1,”cls”:0,”codr”:”4/5″,”data”:”ACflCfz6MZpKFLUABI0AGQ==”,”datr”:”SF9BW125″,”freq”:”868.3″,”lsnr”:”11.2″,”modu”:”LORA”,”rfch”:0,”rssi”:-35,”seqn”:1496,”size”:24,”timestamp”:”2015-10-14T09:49:43Z”,”tmst”:1748894756}

lora/00:00:00:00:00:b9:bd:a5/up {“chan”:7,”cls”:0,”codr”:”4/5″,”data”:”ACfmChX6NfxKFLsABI4ADw==”,”datr”:”SF9BW125″,”freq”:”867.9″,”lsnr”:”11.8″,”modu”:”LORA”,”rfch”:1,”rssi”:-25,”seqn”:1496,”size”:24,”timestamp”:”2015-10-14T09:49:47Z”,”tmst”:1752672436}

lora/00:00:00:00:00:b9:bd:a5/up {“chan”:5,”cls”:0,”codr”:”4/5″,”data”:”ACfmChv6Lv9KFLsABI4ADw==”,”datr”:”SF9BW125″,”freq”:”867.5″,”lsnr”:”9.2″,”modu”:”LORA”,”rfch”:1,”rssi”:-24,”seqn”:1497,”size”:24,”timestamp”:”2015-10-14T09:49:51Z”,”tmst”:1756815268}

lora/00:00:00:00:00:b9:bd:a5/up {“chan”:2,”cls”:0,”codr”:”4/5″,”data”:”ACfmChv6LvpKFLkABI4ADw==”,”datr”:”SF9BW125″,”freq”:”868.5″,”lsnr”:”9.2″,”modu”:”LORA”,”rfch”:0,”rssi”:-23,”seqn”:1498,”size”:24,”timestamp”:”2015-10-14T09:49:55Z”,”tmst”:1760679412}

lora/00:00:00:00:20:00:02:a8/up {“chan”:6,”cls”:0,”codr”:”4/5″,”data”:”mZmZmZmZmZk=”,”datr”:”SF7BW125″,”freq”:”867.7″,”lsnr”:”9.8″,”modu”:”LORA”,”rfch”:1,”rssi”:-33,”seqn”:201,”size”:12,”timestamp”:”2015-10-14T09:50:17Z”,”tmst”:1782111388}

lora/00:00:00:00:00:b9:bd:a5/up {“chan”:1,”cls”:0,”codr”:”4/5″,”data”:”ACfmChX6Nf5KFLkABI4ADw==”,”datr”:”SF9BW125″,”freq”:”868.3″,”lsnr”:”14″,”modu”:”LORA”,”rfch”:0,”rssi”:-25,”seqn”:1503,”size”:24,”timestamp”:”2015-10-14T09:50:17Z”,”tmst”:1782229404}

lora/00:00:00:00:00:b9:bd:a5/up {“chan”:2,”cls”:0,”codr”:”4/5″,”data”:”ACfmChX6Mv9KFLkABI0ADw==”,”datr”:”SF9BW125″,”freq”:”868.5″,”lsnr”:”9.8″,”modu”:”LORA”,”rfch”:0,”rssi”:-19,”seqn”:1506,”size”:24,”timestamp”:”2015-10-14T09:50:29Z”,”tmst”:1794657044}

lora/00:00:00:00:00:0b:e7:16/up {“chan”:2,”cls”:0,”codr”:”4/5″,”data”:”ACflCgL6LppKFLUABI0AGQ==”,”datr”:”SF9BW125″,”freq”:”868.5″,”lsnr”:”9″,”modu”:”LORA”,”rfch”:0,”rssi”:-37,”seqn”:1507,”size”:24,”timestamp”:”2015-10-14T09:50:32Z”,”tmst”:1797312196}

lora/00:00:00:00:00:0b:e7:16/up {“chan”:3,”cls”:0,”codr”:”4/5″,”data”:”ACfkCgL6OJVKFLUABI0AGQ==”,”datr”:”SF9BW125″,”freq”:”867.1″,”lsnr”:”11.8″,”modu”:”LORA”,”rfch”:1,”rssi”:-39,”seqn”:1511,”size”:24,”timestamp”:”2015-10-14T09:50:49Z”,”tmst”:1814848484}

lora/00:00:00:00:00:b9:bd:a5/up {“chan”:2,”cls”:0,”codr”:”4/5″,”data”:”ACflChv6N/tKFLoABI0ADw==”,”datr”:”SF9BW125″,”freq”:”868.5″,”lsnr”:”9.2″,”modu”:”LORA”,”rfch”:0,”rssi”:-22,”seqn”:1514,”size”:24,”timestamp”:”2015-10-14T09:51:03Z”,”tmst”:1828275300}

lora/00:00:00:00:20:00:02:a8/up {“chan”:6,”cls”:0,”codr”:”4/5″,”data”:”mZmZmZmZmZk=”,”datr”:”SF7BW125″,”freq”:”867.7″,”lsnr”:”10.2″,”modu”:”LORA”,”rfch”:1,”rssi”:-33,”seqn”:205,”size”:12,”timestamp”:”2015-10-14T09:51:09Z”,”tmst”:1834681188}

lora/00:00:00:00:00:b9:bd:a5/up {“chan”:6,”cls”:0,”codr”:”4/5″,”data”:”ACfmChv6NwRKFLkABIwADw==”,”datr”:”SF9BW125″,”freq”:”867.7″,”lsnr”:”12.5″,”modu”:”LORA”,”rfch”:1,”rssi”:-27,”seqn”:1516,”size”:24,”timestamp”:”2015-10-14T09:51:11Z”,”tmst”:1836974788}

lora/00:00:00:00:00:b9:bd:a5/up {“chan”:2,”cls”:0,”codr”:”4/5″,”data”:”ACflCiH6LANKFLkABIwADw==”,”datr”:”SF9BW125″,”freq”:”868.5″,”lsnr”:”9.5″,”modu”:”LORA”,”rfch”:0,”rssi”:-27,”seqn”:1518,”size”:24,”timestamp”:”2015-10-14T09:51:20Z”,”tmst”:1845958948}

lora/00:00:00:00:00:b9:bd:a5/up {“chan”:1,”cls”:0,”codr”:”4/5″,”data”:”ACfmCiH6NfpKFLcABIsADw==”,”datr”:”SF9BW125″,”freq”:”868.3″,”lsnr”:”13.5″,”modu”:”LORA”,”rfch”:0,”rssi”:-29,”seqn”:1519,”size”:24,”timestamp”:”2015-10-14T09:51:25Z”,”tmst”:1850140356}

lora/00:00:00:00:00:0b:e7:16/up {“chan”:5,”cls”:0,”codr”:”4/5″,”data”:”ACfkCgL6NJZKFLUABI0AGQ==”,”datr”:”SF9BW125″,”freq”:”867.5″,”lsnr”:”8.2″,”modu”:”LORA”,”rfch”:1,”rssi”:-39,”seqn”:1522,”size”:24,”timestamp”:”2015-10-14T09:51:36Z”,”tmst”:1861479172}

lora/00:00:00:00:00:b9:bd:a5/up {“chan”:4,”cls”:0,”codr”:”4/5″,”data”:”ACflChv6M/9KFLUABIoADw==”,”datr”:”SF9BW125″,”freq”:”867.3″,”lsnr”:”12.8″,”modu”:”LORA”,”rfch”:1,”rssi”:-19,”seqn”:1525,”size”:24,”timestamp”:”2015-10-14T09:51:50Z”,”tmst”:1875727468}

lora/00:00:00:00:00:0b:e7:16/up {“chan”:5,”cls”:0,”codr”:”4/5″,”data”:”ACfkCgL6N5hKFLUABI0AGQ==”,”datr”:”SF9BW125″,”freq”:”867.5″,”lsnr”:”9″,”modu”:”LORA”,”rfch”:1,”rssi”:-39,”seqn”:1530,”size”:24,”timestamp”:”2015-10-14T09:52:10Z”,”tmst”:1895991452}

lora/00:00:00:00:00:b9:bd:a5/up {“chan”:6,”cls”:0,”codr”:”4/5″,”data”:”ACflChv6MANKFLMABIkADw==”,”datr”:”SF9BW125″,”freq”:”867.7″,”lsnr”:”12.2″,”modu”:”LORA”,”rfch”:1,”rssi”:-24,”seqn”:1532,”size”:24,”timestamp”:”2015-10-14T09:52:21Z”,”tmst”:1906394292}

lora/00:00:00:00:00:0b:e7:16/up {“chan”:7,”cls”:0,”codr”:”4/5″,”data”:”ACflCgL6M5lKFLUABI0AGA==”,”datr”:”SF9BW125″,”freq”:”867.9″,”lsnr”:”10.8″,”modu”:”LORA”,”rfch”:1,”rssi”:-41,”seqn”:1533,”size”:24,”timestamp”:”2015-10-14T09:52:24Z”,”tmst”:1909575556}

Corresponding output from the Semtech server over the same time period.

Time Mote Sequence # Freq (MHz) Modulation BW (Hz) SF Coding Rate ADR Gateway Chan RSSI (dBm) SNR (dB)
2015-10-14 09:52:46 00-00-00-00-00-B9-BD-A5 Application data 1532 868.3 LoRa 125 SF9 4/5 off FF-FE-00-00-00-00-00-01 Upstream frames 6 -31 11.8
2015-10-14 09:52:45 00-00-00-00-00-0B-E7-16 Application data 1532 867.3 LoRa 125 SF9 4/5 off FF-FE-00-00-00-00-00-01 Upstream frames 1 -53 13.5
2015-10-14 09:52:42 00-00-00-00-01-0D-EC-AF Application data 210 868.1 LoRa 125 SF7 4/5 off FF-FE-00-00-00-00-00-01 Upstream frames 4 -45 9.5
2015-10-14 09:52:42 00-00-00-00-00-B9-BD-A5 Application data 1531 868.5 LoRa 125 SF9 4/5 off FF-FE-00-00-00-00-00-01 Upstream frames 0 -35 13.5
2015-10-14 09:52:41 00-00-00-00-00-0B-E7-16 Application data 1531 867.1 LoRa 125 SF9 4/5 off FF-FE-00-00-00-00-00-01 Upstream frames 2 -53 8.5
2015-10-14 09:52:38 00-00-00-00-00-B9-BD-A5 Application data 1530 867.5 LoRa 125 SF9 4/5 off FF-FE-00-00-00-00-00-01 Upstream frames 3 -31 11.8
2015-10-14 09:52:36 00-00-00-00-00-0B-E7-16 Application data 1530 867.5 LoRa 125 SF9 4/5 off FF-FE-00-00-00-00-00-01 Upstream frames 5 -45 8.5
2015-10-14 09:52:33 00-00-00-00-00-B9-BD-A5 Application data 1529 867.9 LoRa 125 SF9 4/5 off FF-FE-00-00-00-00-00-01 Upstream frames 5 -33 8.5
2015-10-14 09:52:32 00-00-00-00-00-0B-E7-16 Application data 1529 868.3 LoRa 125 SF9 4/5 off FF-FE-00-00-00-00-00-01 Upstream frames 7 -57 12.2
2015-10-14 09:52:29 00-00-00-00-01-0D-EC-AF Application data 209 867.7 LoRa 125 SF7 4/5 off FF-FE-00-00-00-00-00-01 Upstream frames 1 -49 9.5
2015-10-14 09:52:29 00-00-00-00-00-B9-BD-A5 Application data 1528 868.3 LoRa 125 SF9 4/5 off FF-FE-00-00-00-00-00-01 Upstream frames 6 -37 13.8
2015-10-14 09:52:27 00-00-00-00-00-0B-E7-16 Application data 1528 868.3 LoRa 125 SF9 4/5 off FF-FE-00-00-00-00-00-01 Upstream frames 1 -59 13.5
2015-10-14 09:52:24 00-00-00-00-00-B9-BD-A5 Application data 1527 867.1 LoRa 125 SF9 4/5 off FF-FE-00-00-00-00-00-01 Upstream frames 1 -35 13.8
2015-10-14 09:52:22 00-00-00-00-00-0B-E7-16 Application data 1527 867.7 LoRa 125 SF9 4/5 off FF-FE-00-00-00-00-00-01 Upstream frames 3 -48 12
2015-10-14 09:52:20 00-00-00-00-00-B9-BD-A5 Application data 1526 867.3 LoRa 125 SF9 4/5 off FF-FE-00-00-00-00-00-01 Upstream frames 3 -35 13
2015-10-14 09:52:18 00-00-00-00-00-0B-E7-16 Application data 1526 868.1 LoRa 125 SF9 4/5 off FF-FE-00-00-00-00-00-01 Upstream frames 4 -48 11.5
2015-10-14 09:52:17 00-00-00-00-01-0D-EC-AF Application data 208 867.3 LoRa 125 SF7 4/5 off FF-FE-00-00-00-00-00-01 Upstream frames 0 -51 9.5
2015-10-14 09:52:15 00-00-00-00-00-B9-BD-A5 Application data 1525 867.1 LoRa 125 SF9 4/5 off FF-FE-00-00-00-00-00-01 Upstream frames 4 -33 13.2
2015-10-14 09:52:13 00-00-00-00-00-0B-E7-16 Application data 1525 868.3 LoRa 125 SF9 4/5 off FF-FE-00-00-00-00-00-01 Upstream frames 6 -48 11.2
2015-10-14 09:52:12 00-00-00-00-12-34-56-78 Application data 8 867.7 LoRa 125 SF12 4/5 on FF-FE-00-00-00-00-00-01 Upstream frames 1 -41 10.2
2015-10-14 09:52:11 00-00-00-00-00-B9-BD-A5 Application data 1524 868.3 LoRa 125 SF9 4/5 off FF-FE-00-00-00-00-00-01 Upstream frames 6 -33 13.2
2015-10-14 09:52:09 00-00-00-00-00-0B-E7-16 Application data 1524 868.3 LoRa 125 SF9 4/5 off FF-FE-00-00-00-00-00-01 Upstream frames 1 -55 11.2
2015-10-14 09:52:07 00-00-00-00-00-B9-BD-A5 Application data 1523 867.1 LoRa 125 SF9 4/5 off FF-FE-00-00-00-00-00-01 Upstream frames 1 -33 12.8
2015-10-14 09:52:05 00-00-00-00-00-0B-E7-16 Application data 1523 868.5 LoRa 125 SF9 4/5 off FF-FE-00-00-00-00-00-01 Upstream frames 3 -53 11.2
2015-10-14 09:52:03 00-00-00-00-01-0D-EC-AF Application data 207 867.1 LoRa 125 SF7 4/5 off FF-FE-00-00-00-00-00-01 Upstream frames 2 -41 8
2015-10-14 09:52:03 00-00-00-00-00-B9-BD-A5 Application data 1522 867.5 LoRa 125 SF9 4/5 off FF-FE-00-00-00-00-00-01 Upstream frames 3 -33 12.2
2015-10-14 09:52:01 00-00-00-00-00-0B-E7-16 Application data 1522 867.3 LoRa 125 SF9 4/5 off FF-FE-00-00-00-00-00-01 Upstream frames 5 -53 7.8
2015-10-14 09:51:58 00-00-00-00-00-B9-BD-A5 Application data 1521 867.9 LoRa 125 SF9 4/5 off FF-FE-00-00-00-00-00-01 Upstream frames 4 -33 13.2
2015-10-14 09:51:57 00-00-00-00-00-0B-E7-16 Application data 1521 867.7 LoRa 125 SF9 4/5 off FF-FE-00-00-00-00-00-01 Upstream frames 7 -51 10.8
2015-10-14 09:51:54 00-00-00-00-00-B9-BD-A5 Application data 1520 868.3 LoRa 125 SF9 4/5 off FF-FE-00-00-00-00-00-01 Upstream frames 6 -31 11.5
2015-10-14 09:51:53 00-00-00-00-00-0B-E7-16 Application data 1520 868.3 LoRa 125 SF9 4/5 off FF-FE-00-00-00-00-00-01 Upstream frames 1 -57 13.2
2015-10-14 09:51:50 00-00-00-00-00-B9-BD-A5 Application data 1519 867.1 LoRa 125 SF9 4/5 off FF-FE-00-00-00-00-00-01 Upstream frames 1 -31 12
2015-10-14 09:51:49 00-00-00-00-00-0B-E7-16 Application data 1519 867.3 LoRa 125 SF9 4/5 off FF-FE-00-00-00-00-00-01 Upstream frames 3 -55 12.8
2015-10-14 09:51:48 00-00-00-00-01-0D-EC-AF Application data 206 868.5 LoRa 125 SF7 4/5 off FF-FE-00-00-00-00-00-01 Upstream frames 4 -51 9.2
2015-10-14 09:51:46 00-00-00-00-00-B9-BD-A5 Application data 1518 867.3 LoRa 125 SF9 4/5 off FF-FE-00-00-00-00-00-01 Upstream frames 2 -33 9
2015-10-14 09:51:45 00-00-00-00-00-0B-E7-16 Application data 1518 867.3 LoRa 125 SF9 4/5 off FF-FE-00-00-00-00-00-01 Upstream frames 4 -48 10.2
2015-10-14 09:51:41 00-00-00-00-00-B9-BD-A5 Application data 1517 867.7 LoRa 125 SF9 4/5 off FF-FE-00-00-00-00-00-01 Upstream frames 4 -35 13.2
2015-10-14 09:51:41 00-00-00-00-00-0B-E7-16 Application data 1517 867.7 LoRa 125 SF9 4/5 off FF-FE-00-00-00-00-00-01 Upstream frames 6 -55 11.8
2015-10-14 09:51:37 00-00-00-00-00-B9-BD-A5 Application data 1516 868.3 LoRa 125 SF9 4/5 off FF-FE-00-00-00-00-00-01 Upstream frames 6 -33 12.2
2015-10-14 09:51:36 00-00-00-00-00-0B-E7-16 Application data 1516 867.7 LoRa 125 SF9 4/5 off FF-FE-00-00-00-00-00-01 Upstream frames 1 -57 13.5
2015-10-14 09:51:34 00-00-00-00-01-0D-EC-AF Application data 205 868.1 LoRa 125 SF7 4/5 off FF-FE-00-00-00-00-00-01 Upstream frames 6 -47 9.2
2015-10-14 09:51:32 00-00-00-00-00-B9-BD-A5 Application data 1515 867.1 LoRa 125 SF9 4/5 off FF-FE-00-00-00-00-00-01 Upstream frames 0 -35 13.8
2015-10-14 09:51:32 00-00-00-00-00-0B-E7-16 Application data 1515 868.5 LoRa 125 SF9 4/5 off FF-FE-00-00-00-00-00-01 Upstream frames 3 -55 12.2
2015-10-14 09:51:28 00-00-00-00-00-B9-BD-A5 Application data 1514 867.3 LoRa 125 SF9 4/5 off FF-FE-00-00-00-00-00-01 Upstream frames 2 -30 8.8
2015-10-14 09:51:27 00-00-00-00-00-0B-E7-16 Application data 1514 867.3 LoRa 125 SF9 4/5 off FF-FE-00-00-00-00-00-01 Upstream frames 4 -52 12
2015-10-14 09:51:23 00-00-00-00-00-B9-BD-A5 Application data 1513 868.3 LoRa 125 SF9 4/5 off FF-FE-00-00-00-00-00-01 Upstream frames 4 -35 13.5
2015-10-14 09:51:21 00-00-00-00-01-0D-EC-AF Application data 204 867.9 LoRa 125 SF7 4/5 off FF-FE-00-00-00-00-00-01 Upstream frames 1 -51 9.5
2015-10-14 09:51:19 00-00-00-00-00-B9-BD-A5 Application data 1512 868.1 LoRa 125 SF9 4/5 off FF-FE-00-00-00-00-00-01 Upstream frames 7 -33 12.8
2015-10-14 09:51:19 00-00-00-00-00-0B-E7-16 Application data 1512 867.1 LoRa 125 SF9 4/5 off FF-FE-00-00-00-00-00-01 Upstream frames 0 -57 12.8
2015-10-14 09:51:15 00-00-00-00-00-0B-E7-16 Application data 1511 868.3 LoRa 125 SF9 4/5 off FF-FE-00-00-00-00-00-01 Upstream frames 3 -51 12

Averaging long-term, from the sequence counters, we think the MT device has been receiving 18% of packets, while you can see from the Semtech dump above there are very few missed sequence counts.

Snippet of log files from MT device:

root@mtcdt:~# tail -50 /var/log/lora-network-server.log
9:54:49:217|INFO| Packet accepted from Node 00:0b:e7:16 GW 00:80:00:00:00:00:9a:6a (127.0.0.1) Seq# 61e ADR disabled SF9BW125
9:54:49:217|INFO| Schedule TX Time on air: 164 ms
9:54:53:437|INFO| Parsing 1 rx packets
9:54:53:438|INFO| SeqNo: 0000061f PrevSeqNo: 0000061d Duplicate: no

9:54:53:438|INFO| Addr: 00:b9:bd:a5 MIC Check: passed
9:54:53:455|INFO| Packet accepted from Node 00:b9:bd:a5 GW 00:80:00:00:00:00:9a:6a (127.0.0.1) Seq# 61f ADR disabled SF9BW125
9:54:53:456|INFO| Schedule TX Time on air: 164 ms
9:54:59:515|INFO| Parsing 1 rx packets
9:54:59:516|WARNING| Recv’d frame failed CRC check
9:55:1:748|INFO| Parsing 1 rx packets
9:55:1:749|INFO| SeqNo: 00000621 PrevSeqNo: 0000061f Duplicate: no

9:55:1:749|INFO| Addr: 00:b9:bd:a5 MIC Check: passed
9:55:1:760|INFO| Packet accepted from Node 00:b9:bd:a5 GW 00:80:00:00:00:00:9a:6a (127.0.0.1) Seq# 621 ADR disabled SF9BW125
9:55:1:767|INFO| Schedule TX Time on air: 164 ms
9:55:5:0|INFO| Parsing 1 rx packets
9:55:5:0|WARNING| Recv’d frame failed CRC check
9:55:6:800|INFO| Parsing 1 rx packets
9:55:6:800|WARNING| Recv’d frame failed CRC check
9:55:8:337|INFO| Parsing 1 rx packets
9:55:8:338|INFO| SeqNo: 000000df PrevSeqNo: 000000dc Duplicate: no

9:55:8:338|INFO| Addr: 01:0d:ec:af MIC Check: passed
9:55:8:355|INFO| Packet accepted from Node 01:0d:ec:af GW 00:80:00:00:00:00:9a:6a (127.0.0.1) Seq# df ADR disabled SF7BW125
9:55:8:355|INFO| Schedule TX Time on air: 150 ms
9:55:15:428|INFO| Parsing 1 rx packets
9:55:15:429|INFO| SeqNo: 00000624 PrevSeqNo: 00000621 Duplicate: no

9:55:15:430|INFO| Addr: 00:b9:bd:a5 MIC Check: passed
9:55:15:447|INFO| Packet accepted from Node 00:b9:bd:a5 GW 00:80:00:00:00:00:9a:6a (127.0.0.1) Seq# 624 ADR disabled SF9BW125
9:55:15:447|INFO| Schedule TX Time on air: 164 ms
9:55:20:3|INFO| Parsing 1 rx packets
9:55:20:5|INFO| SeqNo: 00000625 PrevSeqNo: 0000061e Duplicate: no

9:55:20:5|INFO| Addr: 00:0b:e7:16 MIC Check: passed
9:55:20:21|INFO| Packet accepted from Node 00:0b:e7:16 GW 00:80:00:00:00:00:9a:6a (127.0.0.1) Seq# 625 ADR disabled SF9BW125
9:55:20:22|INFO| Schedule TX Time on air: 164 ms
9:55:24:70|INFO| Parsing 1 rx packets
9:55:24:72|INFO| SeqNo: 00000626 PrevSeqNo: 00000625 Duplicate: no

9:55:24:72|INFO| Addr: 00:0b:e7:16 MIC Check: passed
9:55:24:88|INFO| Packet accepted from Node 00:0b:e7:16 GW 00:80:00:00:00:00:9a:6a (127.0.0.1) Seq# 626 ADR disabled SF9BW125
9:55:24:89|INFO| Schedule TX Time on air: 164 ms
9:55:31:362|INFO| Parsing 1 rx packets
9:55:31:363|INFO| SeqNo: 000000e1 PrevSeqNo: 000000df Duplicate: no

9:55:31:363|INFO| Addr: 01:0d:ec:af MIC Check: passed
9:55:31:380|INFO| Packet accepted from Node 01:0d:ec:af GW 00:80:00:00:00:00:9a:6a (127.0.0.1) Seq# e1 ADR disabled SF7BW125
9:55:31:380|INFO| Schedule TX Time on air: 150 ms

root@mtcdt:~# tail -50 /var/log/lora-pkt-fwd.log
# CRC_OK: 66.67%, CRC_FAIL: 33.33%, NO_CRC: 0.00%
# RF packets forwarded: 6 (349 bytes)
# PUSH_DATA datagrams sent: 6 (1748 bytes)
# PUSH_DATA acknowledged: 0.00%
### [DOWNSTREAM] ###
# PULL_DATA sent: 2 (100.00% acknowledged)
# PULL_RESP(onse) datagrams received: 0 (0 bytes)
# RF packets sent to concentrator: 0 (0 bytes)
# TX errors: 0
##### END #####
INFO: [down] PULL_ACK received in 1 ms

##### 2015-10-14 09:55:44 GMT #####
### [UPSTREAM] ###
# RF packets received by concentrator: 1
# CRC_OK: 100.00%, CRC_FAIL: 0.00%, NO_CRC: 0.00%
# RF packets forwarded: 1 (21 bytes)
# PUSH_DATA datagrams sent: 1 (239 bytes)
# PUSH_DATA acknowledged: 0.00%
### [DOWNSTREAM] ###
# PULL_DATA sent: 1 (100.00% acknolgw_receive:1428: FIFO content: Pkts: 1 69 3 Stat: 7 Size: fe
lgw_receive:1443: [5 17]
Note: LoRa packet
lgw_receive:1428: FIFO content: Pkts: 1 77 0 Stat: 5 Size: 15
lgw_receive:1443: [3 17]
Note: LoRa packet
lgw_receive:1428: FIFO content: Pkts: 1 9c 0 Stat: 5 Size: 1d
lgw_receive:1443: [5 17]
Note: LoRa packet
lgw_receive:1428: FIFO content: Pkts: 1 c9 0 Stat: 5 Size: 1d
lgw_receive:1443: [0 17]
Note: LoRa packet
lgw_receive:1428: FIFO content: Pkts: 1 f6 0 Stat: 5 Size: 1d
lgw_receive:1443: [6 17]
Note: LoRa packet
lgw_receive:1428: FIFO content: Pkts: 1 23 1 Stat: 5 Size: 1d
lgw_receive:1443: [4 17]
Note: LoRa packet
lgw_receive:1428: FIFO content: Pkts: 1 50 1 Stat: 5 Size: 1d
lgw_receive:1443: [2 17]
Note: LoRa packet
lgw_receive:1428: FIFO content: Pkts: 1 7d 1 Stat: 5 Size: 1d
lgw_receive:1443: [0 17]
Note: LoRa packet
lgw_receive:1428: FIFO content: Pkts: 1 aa 1 Stat: 5 Size: 1d
lgw_receive:1443: [2 17]
Note: LoRa packet
lgw_receive:1428: FIFO content: Pkts: 1 d7 1 Stat: 5 Size: 15
lgw_receive:1443: [2 17]
Note: LoRa packet

Happy to provide more info, we’ll keep the network up for the next few days.

[Antony Rix]

Also I should note that we have a spectrum analyser up monitoring the band, and can rule out interference causing this.

Oddly, plotting a histogram of the number of packets received by the MT gateway by LoRa channel, there is a massive difference – two channels have high probability of reception, the others much lower. Maybe we have a dud gateway radio?

[Brandon Bayer]

Antony,

Thank you very much for all info and logs! We’ll look through it further, but you may want to try changing the network server config’s public option to true. This changes the sync word from 0x12 to 0x34. The sync word is the first byte in the preamble and is used to distinguish between networks. If the sync word is incorrect, the radio shouldn’t receive them at all, but in practice, we’ve seen it actually receive a low percentage of packets in this case.

-Brandon

[Antony Rix]

Hi Brandon,

Well spotted. I’ve changed “public” to “true” and can also confirm that the LoRaMotes were set up to public, not private.

We are trying this and it’s looking rather better so far. 50 packets received from our most chatty test node with 0 losses.

So the odd thing seems to be that we received the packets at all, when the syncword was set incorrectly!

We’ll do a longer test tomorrow and will report again.

Kind regards,

Antony

[Antony Rix]

Hi Brandon,

Yes, it seems that the syncword was the issue here. We ran a long test overnight with over 20,000 packets from 3 LoRa nodes, and found at least 99% successful reception rate at the Conduit gateway (though at close range).

We’re now working on getting the downlink working to one of our Semtech LoRa mbed platforms running the Alliance codebase. This direction is also currently unreliable, and we’re aware of the need to match the data rate configuration of the RX1 and RX2 windows at both ends. Again, any suggestions very welcome.

Kind regards,

Antony

[Brandon Bayer]

Antony,

Good to hear!

Unless you got your MTAC-LORA card recently, it could have a problem transmitting (super low range).

You can run this test with an mDot to evaluate it:

1) Place Conduit & mDot right beside each other
2) Take antennas off mDot & Conduit
3) Set Conduit tx power to 26
4) Set mDot tx power to 20
5) Have mDot join network
6) On mDot issue, AT+PING then AT+RSSI and send us the output of these two commands.

The RSSI response should be higher than PING because the Conduit is transmitting at a higher power.

-Brandon

[Antony Rix]

Hi Brandon,

Thanks for your help.

We’ve done this with an mdot at the standard transmit power.
AT+PING returned -22,10
We didn’t do AT+RSSI and the mdot isn’t connected at the moment but I will check and post again when it is.

Presuming that’s -22dBm (the devices are near each other), it’s a similar received power to what we see on our Semtech gateway. Is this OK?

We will be doing a proper RF calibration of both ends’ transmit power and receive level vs. RSSI next week as we have the equipment here to do so.

Through some fiddling around we now have our mdot and Semtech boards successfully joining, and are able to send packets down to the Semtech board (essentially, implementing a more sophisticated PING at present).

Looking good at the moment, and I hope to update you again soon.

Antony

[Brandon Bayer]

Alright, sounds good! Keep us updated.

-Brandon

[Antony Rix]

Hi Brandon,

I just wanted to confirm that we are confident that the issue was the public/private network configuration, and correcting this we get expected sensitivity and link budget in both uplink and downlink directions.

The Conduit is working well, and needed little more than a few lines of shell code to implement our specific test application requirements.

Another thing that we found may be helpful for others.

We spotted and are currently working through the implications of the two receive slots in the LoRaWAN protocol. Do we have any way of controlling which of the slots are used by the Conduit? It appears to use both, which consumes a lot of downlink resource; you would ideally use only the +27dBm 869.525MHz downlink channel at high data rate, to work around the EU duty cycle restrictions. As I understand it, the protocol allows the gateway to choose which to use and does not mandate dual transmission. Specifically we’re trying to get radio attenuation readings for range testing, and because the receiver sometimes gets the packet on different channels sent with different powers and modulations, it has the potential to confuse our measurements.

Antony

[Brandon Bayer]

Antony,

Great!

The gateway will always use the first window only except when there is a tx scheduling conflict. In that case, it’ll use only the second window. It should never transmit during both windows. And there is no way to reconfigure this behavior.

-Brandon

[Antony Rix]

Hi Brandon,

Very helpful to know, many thanks.

Antony

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