Narrowband IoT:

Narrowband IoT:

Perspective on Battery Powered Use-Cases

Presented by: Dr. Pavel Masek

March 19, 2019

O

• Narrowband IoT (NB-IoT)

o Current situation on the market in Czech Republic

• Constructed NB-IoT prototypes

o Verification in specialized chambers

• Power consumption in real use-cases

o Sigfox o NB-IoT

• Up-to-date network coverage for available LPWA technologies in Czech Republic

o Sigfox

3

O

P

N

I

T T

• Industrial grade technology

o Maximum Coupling Loss (MCL) 164 dB o Flexible power management (eDRX, PSM)

• Already a proven choice for Industry 4.0

o Higher speeds and flexible for carriers to deploy o Broad market support as an open 3GPP

standard

• Secure and available

o LPWA security matters (LTE security stack implemented)

o Proprietary LPWA technologies do not provide enough coverage as they use private network infrastructure

N

I

T (NB-I

T)

• Key features of NB-IoT

o 10 years on-premise life expectancy o 10 km communication range

o Less than 10 € per chip

o More than 10k devices support

o Complete coverage in Czech Republic (03/2019)

5

C

LPWA

(03/2019)

LoRa Sigfox NB-IoT

Coverage 154dB 162dB 164dB

Technology Proprietary Proprietary Open LTE

Spectrum Unlicensed Unlicensed Licensed (LTE/any)

Duty cycle limit. Yes Yes No

Output power

restrictions Yes (14dBm=25mW) Yes (14dBm=25mW)

No

(23dBm=200mW) Downlink data rate 0.3-50kbps <1kbps 0.5-27.2kbps

Uplink data rate 0.3-50kbps <1kbps 0.3-32.25kbps Battery life / Current

consumption

8+ years

<2uA

10+ years

<2uA

10+ years

<3uA

Module cost <$10 <$10

$10 (2019) to <$3 (2020)

Security Medium (AES-128) Low (AES-128)

Very high (LTE Security)

NB-I

T – D

P

(

B

, Q

)

• Life expectancy of NB-IoT above 20 years, keeping the cost and power

consumption low, with limited data throughput

• Low power consumption delivering 10+ years battery life

• Prototype is designed that it can be used in areas beyond the radio coverage of current cellular standards

7

L

S

NB-I

T V

– U

C

• NB-IoT Uplink Channel (Band 20; Vodafone)

o Frequency: 861.7 MHz o EARFCN: 24447

9

NB-I

T V

– D

C

• NB-IoT Downlink Channel (Band 20; Vodafone)

o Frequency: 820.7 MHz o EARFCN: 6447

NB-I

T V

– EMC C

• Interference measurement in EMC chamber

o Band 20 (820 – 870 MHz)

o Continuous interferences from embedded board -- without significant impact

11

P

M

• DC power analyzer Agilent N6705A was utilized for current measurements

• Consumption was measured through dedicated test pins on custom-designed board

• Shield box R&S CMW

o Frequency range up to 6 GHz

• Sampling interval 0.02 ms

• Measurement scenario for NB-IoT

o Message size: 12B (max. 512B vendor-specific) o Transmission interval: 30s

o Number of messages sent: 10

o Release assistance: ON (flag 0x200)

o All statistic logged on the dedicated server

P

M

– NB-I

T (

R

A

)

• NB-IoT module power consumption with default settings; message size 12B

• Energy required for transmission 0.083 J

13

P

M

– S

• Sigfox module power consumption with default settings; message size 12B

• Energy required for transmission 1.191 J

F

T

C

B

(03/2019)

• 100 measurements points where all available LPWA technologies were tested

o Sigfox, LoRaWAN (CRa), LoRaWAN (BUT), Narrowband IoT

15

F

T

C

B

– NB-I

T (03/2019)

• 100 measurements

• NB-IoT setup for each measurement point

o Message size: 12B o Transmission

interval: 30s o Number of

messages sent: 10 o Release

assistance ON (flag 0x200)

o All statistic logged on the dedicated server

NB-IoT RSSI

-135 dBm -40 dBm

F

T

C

B

– S

(03/2019)

• 100 measurements

• Sigfox setup for each measurement point

o Message size: 12B o Transmission

interval: 60s o Number of

messages sent: 5 o Repetition: each of

the messages are sent 3 times on

Sigfox RSSI

-135 dBm -40 dBm

17

P

C

. T

. D

1/2

• Measurements

conducted in Vötsch VC3 7018

temperature chamber

o Temp. range for tests from -72°C to +180 °C

• Module heated up to 92 °C and then

cooled down to -18 °C

P

C

. T

. D

2/2

• Significant growth of power consumption with rising temperature

• Current consumption growth is caused by natural behavior of semiconductor junction

• At 85 °C consumption raised up to 25 uA, which is more then 6 times higher consumption compared to 25 °C

• Increase in consumption during cooling is caused by temperature hysteresis

19

L

L

• Narrowband IoT

o Message size: 12B o Signal level: -80dBm

o Energy per message: 0.083J

NB-IoT RSSI

-135 dBm -40 dBm

Sigfox RSSI

-135 dBm -40 dBm

• Sigfox

o Message size: 12B; TX PWR: 14dBm o Signal level: -100 dBm

o Energy per message: 1.191J

C

- B

L

E

(NB-I

T

. S

)

• 2600 mAh (SAFT LS 14500) lithium battery with spiral wound construction is considered; message size 12B

o Calculations do involve battery self-discharging (about 1% per year)

8

14

23

34 30

35 37 39

10 15 20 25 30 35 40 45

ted battery life [years]

Sigfox NB-IoT

Thank you for your attention.

pavel.masek@triwave.tech masekpavel@vutbr.cz

21

T

W

T

.

.

.

• Startup company with Brno University of Technology

• Founded in 2018

• Contact: pavel.masek@triwave.tech

• Web: http://www.triwave.tech/

• Location: Purkynova 649/127, Medlanky, 612 00 Brno South Moravian Innovation Centre

• Ongoing cooperation with industry partners