LoRaWan is a wireless communication protocol built on top of the LoRa modulation technique. It allows long-range transmissions of small amounts of data at low bit rates. The Things Network is an open global network that allows devices connected to it to communicate using the LoRaWan protocol. It has an open-source, decentralized architecture and over 6000 members, 2000 gateways across 55 countries. Common applications include smart bins, flood detection networks and fluid level monitoring.

1. LoRaWan & The Things Network
Romain Cambier - Shareif.com

2. About me
Romain Cambier - @r_cambier
CS Engineer from Mons (172), BE
Founder & Owner of Shareif.com
The Things Network Ambassador

3. Wireless TechnologiesBandwidth
Range
VSAT
2G
3G
4G
ZigBee
802.15.3
802.15.4
RFID
NFC
BlueTooth
BLE
802.11.a/b/g
802.11.ac/n
Tens of meters Hundreds of meters Thousands of meters
LPWAN
> 1 Mbps
> 100 Mbps
<< 1 Mbps

4. LoRa ≠ LoRaWan

5. What is LoRa ?
● Wireless modulation
● Radio physical layer
● Low bandwidth & energy
● Uses ISM bands
● Great link budget (> 150 dB)

6. What is LoRaWan ?
● Communication protocol built above LoRa modulation
● Data rate from 300 bps to 5.5 kbps (up to 50kbps
using FSK)
● Features :
– Bi-directional communication
– Mobility
– Localization

7. LoRa(Wan)

8. History
● 2007 : Nanoscale-Labs
● 2009 : Cycleo
● 2012 : Semtech
● 2015 : LoRa Alliance

9. Radio Basics

10. Radio Keying : OOKTime
Frequency

11. Radio Keying : FSKTime
Frequency

12. Radio Keying :PSKTime
Frequency

13. Spread Spectrum

14. Chirp Spread Spectrum
Time Frequency

15. Chirp Spread Spectrum
Chirp frequency :

16. LoRa

17. LoRa Modulation
● Spread-spectrum technique and a variation of chirp
spread spectrum (CSS)

18. Chirp Spread Spectrum in LoRa
Time
Frequency

19. Chirp Spread Spectrum in LoRa
Phase shiftings
= where the data is
~ PSK over chirp

20. LoRa demodulation
x =

21. LoRa demodulation, with noise
x =

22. LoRa Modulation
● Spread-spectrum technique and a variation of chirp
spread spectrum (CSS)
● LoRa uses Spreading Factors to set the modulation
rate (SF7 to SF12)

23. LoRa Spreading Factors
SF7
SF8
SF9
...

24. LoRa Spreading Factors
Spreading Factor Symbols/second Bitrate TOA (10 bytes, ms) SNR limit (dB)
SF 7 976 5469 56 -7,5
SF 8 488 3125 103 -10
SF 9 244 1758 205 -12,5
SF 10 122 977 371 -15
SF 11 61 537 741 -17,5
SF 12 30 293 1483 -20

25. Benefits of the Modulation
● Very resistant to interferences
● Very low sensibility to fading & multipath
● Good sensitivity (below noise level)
● Doppler effect resistant
– Moving devices
– High clock tolerance
● LoRa reception is super simple

26. FSK Modulation
● Same idea as PSK
● Modulate frequency instead
● Higher sensibility to :
– Moving devices
– Bad clock sync
– Random interferences

27. FSK Modulation
● Same idea as PSK
● Modulate frequency instead
● Higher sensibility to :
– Moving devices
– Bad clock sync
– Random interferences

28. LoRaWan

29. LoRaWan protocol : Device class
● Class A
– Emit on request, listen only after emit → ultra-low energy
● Class B
– Emit on request, listen based on time interval → low energy
● Class C
– Emit on request, always listen → « high » energy

30. LoRaWan Network Architecture

31. LoRaWan protocol :
authentication
ABP :
● Dev addr
● AppSKey
● NwkSKey
OTA :
● DevEUI
● AppEUI
● AppKey
● AppSKey and NwkSKey
derivated from AppKey &
Network response

32. LoRaWan Network Encryption

33. LoRaWan protocol : Messages
● Join Request (AppEUI, DevEUI, DevNonce)
● Join Accept (AppNonce, NetId, DevAddr, DLSettings, RxDelay,
CFList)
● UnConf data up (your data)
● UnConf data down (your data)
● Conf data up (your data)
● Conf data down (your data)
● RFU / Proprietary

34. LoRaWan protocol
preamble phdr phdr_crc phy PL crc
mhdr mac PL mic
fhdr fport frm PL
dev addr fctrl fcnt fopts
mtype rfu major
Can contains
MAC commands

35. LoRaWan protocol : MAC
commands
● LinkCheckReq, LinkCheckAns = connectivity check
● LinkADRReq, LinkADRAns = change emit settings like SF
● DutyCycleReq, DutyCycleAns = update device DC
● RXParamSetupReq, RXParamSetupAns = change RX window
● DevStatusReq, DevStatusAns = get dev. status like battery
● NewChannelReq, NewChannelAns= channel upadte
● RXTimingSetupReq, RXTimingSetupAns = change RX window

36. LoRaWan Network Architecture

37. LoRaWan Network : Devices
● Joining the network (if OTAA)
● Converting your payload as a LoRaWan packet
● Sending the packet
● Listening for downlink packets
● Converting the packet back to payload

38. LoRaWan Network : Gateways
● Receiving radio packets
● Checking CRC (message integrity, only for uplink)
● Forwarding to network server
● Listening for downlink messages to forward to devices

39. LoRaWan Network : Network
Server
● Dealing with join requests
● Dealing with devices addresses
● Choosing time and gateways to use for downlink
● En/Decrypting MAC payload

40. LoRaWan Network : App. Server
● Receiving packets from devices
● Scheduling responses to devices
● En/Decrypting FRM Payload (the real payload)
● In fact, do something with the data...

41. LoRaWan Network : Localisation
● Triangulation
– Accuracy (3gw) :
→ ~ 180 m in crowded area
→ ~ 350 m in clear area
– Accuracy (4gw)
→ ~ 95 m in crowded area
→ ~ 210 m in clear area
From semtech

42. LoRaWan Network : Localisation
● Triangulation
● Big-Data
– Accuracy (3gw) :
→ ~ 35 m in crowded area
→ ~ 220 m in clear area
– Accuracy (4gw)
→ ~ 22 m in crowded area

43. LoRaWan protocol : Duty Cycle
● The more messages on the same frequency & SF =
the higher collision probability
● We want reliable transmission
● We want a lot of devices per gateway (>1000)
→ we need the keep the collision probability low
enough !
→ Typically, < 10 % or even < 5 %

44. LoRaWan protocol : Duty Cycle
● A gateway listen on 8 frequencies and all SF
● We want > 1000 devices / gateway
● We want < 10% of duty cycle
→ 30 seconds / day / devices gives a DC < 5%

45. LoRaWan protocol : Duty Cycle
● Rule: max. 30 seconds/device/day
● For a 10-bytes PL we have max:
– 20 messages/day at SF12
– 500 messages/day at SF7
– Much more using SF7-250 or FSK modulation (lower range & higher
energy)
● Downlink is limited to < 10 messages/device/day

46. LoRaWan protocol : ADR
Spreading Factor SNR limit (dB)
SF 7 -7,5
SF 8 -10
SF 9 -12,5
SF 10 -15
SF 11 -17,5
SF 12 -20
● Reception of a packet on
SF12 with SNR = -7,5dB
● Check the best SF with a
margin of 5dB
● Send MAC command to request
SF9 on the device

49. The Things Network : Principles
● Standards compliant
● Compliant with spectrum regulations
● Open source
● Designed for distribution and decentralization
● One global, free and open network

50. The Things Network : History
● Jul. ‘15 : Announce of The Things Network
● Sept. ‘15 : First gateways installed in Amsterdam
→ Croft environment started
● Oct. ‘15 : KickStarter campaign started
● Nov. ‘15 : KickStarter end with > 2x funding!
● Mar. ‘16: Staging environment setup

51. The Things Network :
Architecture
R
Router
Routes raw packets
from gateways to
brokers
NC
Network Controller
Node state: data rate
and frequency
management
H
Application Handler
Decryption, deduping,
works on behalf of
apps
A
Application
User application
Gateway
Send data to and
receive data from
nodes
B
Broker
Decoupling from
Router and Application
Handler

52. The Things Network :
Architecture
H
S1, S2
S2, S1, S3
S2, S1, S3
S3, S2
B
R
ANC
Private Network
B
R NC
HBR
NC
H
H
H
NR
A
A
Private Storage Handler
A

53. The Things Network : Gateways

54. The Things Network : Projects
● LoRaWan over BLE
● LoRaWan over 802.15.4
● M-Bus over LoRa(Wan)

55. The Things Network : Numbers
● > 6,000 members
● > 2,000 gateways
● > 200 communities
● > 55 countries
... and counting !

56. The Things Network : Coverage

57. The Things Network : Coverage

58. The Things Network : Coverage

59. 352 KM
160 KM
LoRaWan : Performance

60. The Things Network :
Applications
ComeEmpty.Me

61. The Things Network :
Applications
SmartBin.com

62. The Things Network :
Applications
FLUID

63. The Things Network :
Applications

64. The Things Network :
Applications
flood.network

65. LoRaWan & The Things Network
Romain Cambier - Shareif.com

66. Sources
● Thomas Telkamp - LoRa crash course – 10 Nov. ‘16
● Matt Knight - Decoding LoRa – 05 Oct. ‘16
● Johan Stokking – The Things Network – Jul. ‘15
● TTNMapper.org – Nov. ‘16