Support de présentation : Introduction to NB IoT

1. Introduction to NB IoT
Nicolas Tribie – ntribie@sequans.com
Copyright © 2018 Sequans Communications
MKT-FM-016-R01

2. LTE (4G) for IoT Usage
Copyright © 2018 Sequans Communications2
Nokia
3GPP

3. NB IoT versus LoRaWAN
3
Licensed Spectrum
 Users need to register with an operator.
 Guaranteed QoS
Reuses existing 4G base stations network
 NB IoT support : By software upgrade,
 Network is costly , but shared with 4G usage
 Natural replacement for GPRS M2M
Higher power consumption
 Protocol overhead (QoS)
Unlicensed Spectrum
 Private networks are possible
 Also deployed by operators
 Spectrum shared with other devices
New network deployment required
 But Low cost base stations.
Lower power consumption
 Small protocol overhead
NB IoT LoRaWAN
Similar Data Throughput
Similar coverage performance

4. NB IoT Performance
4
50 000 to 800 000 devices per base station (eNB)
~ 10 new connexions / second per base station
< 10 s latency
Coverage :
 ~1.5 km urban (Need to reach basement water/electricity meters )
 20 km free range
 3x GSM / legacy LTE ( 164 dB MCL)
10+ years battery life
 200 Bytes upload, 20 bytes download / day / 5WH battery Coverage (km) . 3GPP

5. LTE Signal: OFDM Modulation
5
5 to 20 MHz BW for LTE
Sound Analogy: Multiples notes of a piano chord
 Message = intensity of a single note + notes sequence
Light Analogy: White light decomposition in a rainbow
 Message = intensity of each monochromatic source + sequence
Usages: LTE, WiFi, DVB-T (digital TV) , ADSL , PowerLine, ..

6. LTE signal structure
Copyright © 2015 Sequans Communications6
P-SCH - Primary Synchronization Channel
S-SCH - Secondary Synchronization Channel
PBCH - Physical Broadcast Channel
PDCCH - Physical Downlink Control Channel
PDSCH – Physical Downlink Shared Channel
Reference Signal – (Pilot)
64QAM16QAM QPSK
Frequency
Time
Agilent

7. OFDMA : Spectrum Sharing Between Users
7
Agilent

8. NB IoT in the LTE signal
8
One Physical resource Block (PRB) is assigned to NB IoT traffic : 12 subcarriers
NB IoT devices will only listen to this tiny 180 KHz bandwidth
 Simpler Radio , lower power
 Only 1 % of the total LTE bandwidth
NB IoT
Frequency
Time
Agilent

9. In Real Life : LTE Spectrum
9
Frequency
Time
Signal from an Enode-B (base station) , seen from a spectrum analyzer
NB IoT

10. Messaging sequence
• Wake up
• Synchronize with Network
• Get Network Info
• Request Access
• Setup session
• Data exchange
• Close Session
• Re-enter deep sleep
3GPP

11. NB ioT vs LTE Coverage enhancements
11
LTE signal originally designed for :
 High Data throughput (> 100 Mbps) , fair reception conditions
 Fairly complex receiver (costly)
 “High” power consumption (mobile battery : 8 WH)
NB IoT is targeted for :
 Low cost and Low Power Devices,
 Low data throughput , bad reception conditions
Solution : Transmission repetitions:
 Simpler coding : “simpler” receiver,
 Signal is compatible with LTE freq/time grid
 Signal / Noise is improved across repetitions
 Throughput / coverage tradeoff tailored to each case :
 -100 dBm (fair RX conditions) : 1 repetitions : ~ 56 Kbps
 -144 dBm (worst RX condition) :256 repetitions : ~ 400 bps
Analogy with Astronomy Photography
(faint Galaxy image acquisition)

12. Energy savings Enhancements
Copyright © 2015 Sequans Communications12
Concept : stay idle as long as possible
 A periodic RendezVous is negotiated
with the base station :
 Base station keeps the device registered
 Device remembers network parameters
 Shorter attach time
 Device goes into sleep mode,
 Device wakes up quickly at each RDV:
 Data exchange happens
 QoS : NBioT claims less energy spent per
message than LoRaWAN
Device can request uplink at anytime
 Example : sensor alert
3GPP

13. Sequans NB IoT Platform
13
• Hardware : Paris
• RF : Reading (UK) / Kista (SW)
• SW / DSP : Sophia/ Paris
Pycom “FiPy”module for Makers
WiFi/BT CatM NB-IoT
Sequans Monarch Platform
PyCom
Sequans

14. Towards 5G..
14
Source: ITU
Cat-M and NB-IoT fulfill 5G mMTC requirements:
mMTC : Massive Machine Type
Communications
MultiCast capability added
Even more power savings features

15. 15
Thank You !
References :
 www.sharetechnote.com/html/Handbook_LTE.html
 Book: Cellular Internet of Things:
 Slideshare: Tdd lte training material
 3GPP: www.3gpp.org

16. Annex 1 :NB IoT Frame
16
Time view
User control
User Data

17. Annex 2.1 : Energy consumption Lora / NB IoT
17
Actility

18. Annex 2.2: Energy Timeline
18

19. Annex 3 :Link Budget details
19

20. Annex 4 : Throughput
20