Measuring the performance of Narrowband-IoT (NB-IoT) Ahmed - - PowerPoint PPT Presentation

▶
measuring the performance of narrowband iot nb iot
SMART_READER_LITE
LIVE PREVIEW

Measuring the performance of Narrowband-IoT (NB-IoT) Ahmed - - PowerPoint PPT Presentation

Jan 29, 2024 110 likes •295 views

Measuring the performance of Narrowband-IoT (NB-IoT) Ahmed Elmokashfi, Foivos Michelinakis and Anas Al-selwi IoT applications have diverse requirements Shorter to medium battery life Battery life 5-10 years Ubiquitous outdoor coverage Medium

slide-1
SLIDE 1

Ahmed Elmokashfi, Foivos Michelinakis and Anas Al-selwi

Measuring the performance of Narrowband-IoT (NB-IoT)

slide-2
SLIDE 2

IoT applications have diverse requirements

2

Shorter to medium battery life Medium coverage Some mobility Latency in order of seconds Battery life 5-10 years Ubiquitous outdoor coverage Some mobility Medium to high reliability Latency < 10 seconds Battery life 10-15 years Outdoor and deep indoors (+20dB) Stationary Medium to high reliability Latency 10 to 60 seconds Mains powered Outdoor and indoors Stationary low to high reliability Latency < 30 seconds

GSMA white Paper. 3GPP Low Power wide Area Technologies

slide-3
SLIDE 3

Mobile-IoT must be scalable, energy efficient and ubiquitous

3

slide-4
SLIDE 4

3GPP Release 13 standardized two solutions for current and future IoT

4

NB-IoT LTE Cat. NB eMTC LTE Cat. M1 Deployment In-Band LTE, guard- band LTE and standalone In-Band LTE Bandwidth 180 KHz 1.08 MHz Peak data rate ~150 kbps 1 Mbps Latency 1.6s-10 s 10-15 ms Max UE tx power 23 or 20 dBm 23 or 20 dBm Power Saving PSM, eDRX PSM, eDRX Duplex Half Full/Half Complexity relative to LTE 10% 20-25%

3GPP Release 13 standardized two solutions for current and future IoT

30

NB-IoT LTE Cat. NB eMTC LTE Cat. M1 Deployment In-Band LTE, guard- band LTE and standalone In-Band LTE Bandwidth 180 KHz 1.08 MHz Peak data rate ~150 kbps 1 Mbps Latency 1.6s-10 s 10-15 ms Max UE tx power 23 or 20 dBm 23 or 20 dBm Power Saving PSM, eDRX PSM, eDRX Duplex Half Full/Half Complexity relative to LTE 10% 20-25%

  • NOKIA. LTE-M – Optimizing LTE for the Internet of Things, 2015
slide-5
SLIDE 5

NB-IoT is now deployed in several countries

5

Image source GSMA

slide-6
SLIDE 6

NB-IoT has two mechanisms to help devices conserving power

6

  • Whilst it has always been possible for a device’s application to turn its radio module off to
  • GSMA. NB-IoT DEPLOYMENT GUIDE to Basic Feature set Requirements April 2018
slide-7
SLIDE 7

NB-IoT enhances coverage by using transmission repetitions

7

§ 2x repetitions translates into 3dB coverage gain § 2x repetitions results in 0.5x speed and 2x latency

slide-8
SLIDE 8

Early measurements of NB-IoT commercial deployments

8

§ 2 mobile operators + 2 NB-IoT modules § UDP ping every minute with packet sizes in the range 20 to 512 bytes

slide-9
SLIDE 9

Measurements traffic pattern

9

Active paging Connecting & sending Idle paging PSM Measurement id

slide-10
SLIDE 10

Clear differences in energy consumption between operators and devices

10

These differences can reduce battery lifetime by 6 years (assuming that we are using a CR2032 battery with 235mAh capacity and 1 activity period per day )

0.05 0.1 0.15 0.2 0.25 1 10 Probability density Energy [J] Operator I-Device I Operator I-Device II Operator II-Device I Operator II-Device II

slide-11
SLIDE 11

The differences are also evident when the coverage is poor

11 0.1 0.2 0.3 0.4 0.5 0.6 1 10 Probability density Energy [J] Operator I-Device I Operator I-Device II Operator II-Device I Operator II-Device II

slide-12
SLIDE 12

The two operators configure power management differently

12

Measurement id

slide-13
SLIDE 13

The two operators configure power management differently

13

Measurement id

slide-14
SLIDE 14

RTTs are mostly below 10 seconds but are characterized by wide variability

14

0.1 0.2 0.3 0.4 0.5 0.6 0.7 0.8 0.9 1 1 10 Fraction of packets RTT (sec) Operator I-Device I Operator I-Device II Operator II-Device I Operator II-Device II

slide-15
SLIDE 15

Achieving a similar delay may correspond to different energy consumption levels

15

1 2 3 4 5 6 7 8 9 10 1 10 Energy [J] RTT (sec) Operator I-Device I Operator I-Device II Operator II-Device I Operator II-Device II

slide-16
SLIDE 16

RTT variability can partially be attributed to differences in coverage

16

  • 150
  • 100
  • 50

50 100 150 200 1 10 SNR (dBm) RTT (sec) Operator I-Device I Operator I-Device II Operator II-Device I Operator II-Device II

slide-17
SLIDE 17

Probability (RTT|Energy consumption)

17

1 2 3 4 5 6 7 8 9 2 4 6 8 10 12 Battery lifetime (years) RTT (sec) 0.1 0.2 0.3 0.4 0.5 0.6 0.7 0.8 0.9 2 4 6 8 10 12 Fraction of packets with RTT>x RTT (sec) Operator I-Device I Operator I-Device II Operator II-Device I Operator II-Device II

What is my target battery lifetime? How likely I get RTTs higher than max? What is corresponding max RTT?

slide-18
SLIDE 18

There is a need for new metrics for describing NB-IoT reliability and performance

18

§ Several questions remain unanswered

  • Can we generate realistic traffic patterns?
  • Understand how transport protocols perform
  • ver NB-IoT e.g. COAP, MQTT

§ NB-IoT large parameter space makes interpreting measurements difficult

  • Power management timers
  • Repetitions