Nokia Research Center

High Accuracy Indoor Positioning Based on BLE

Kimmo Kalliola

Research Leader

April 27, 2011

Nokia Research Center

Motivation for Indoor Positioning

• Location based services are growing enabled by mobile devices with GPS

• People spend most of the time indoors

• No wide-spread indoor positioning systems and services are available yet

• GPS operation is very limited indoors

• Personal communication devices can enable indoor positioning through local wireless networks

• Big market opportunity in indoor location based services, such as targeted advertising

People spend 80-90% of their time indoors

70% of cellular calls and 80% of data connections originate from indoors.

(Source Strategy Analytics)

Time spent …

2

Nokia Research Center

Indoor Navigation needs

Who’s around?

Where to find milk?

How to get there? What can I find here?

Where did I leave my car?

Where is the closest

restaurant?

3

Nokia Research Center

WiFi Positioning

• Based on measuring the relative received signal strength (RSS) from WiFi access points at the mobile

• Available today in many smartphones but with limited accuracy

• Location accuracy typically 30 – 50 meters

• Adequate for local search but not for indoor navigation

• Limited coverage and accuracy inside large indoor spaces due to automatic data collection

• Floor information not available

• Used for asset tracking in specific environments, such as hospitals

• Provides room level accuracy with good probability

• Requires manual calibration

• Challenges:

• Achieving high accuracy in large open indoor spaces – such as malls, supermarkets, or airports – is challenging due to radio signals propagating easily large distances

• Accuracy is deteriorated by directional handset antennas, which affect the relative AP signal strengths

• Practical maximum reachable accuracy is 3-10 meters depending on environment

4

Nokia Research Center

5

HAIP – High Accuracy Indoor Positioning

Nokia Research Center

HAIP – Location Enhanced Bluetooth Technology

• Built on top of Bluetooth Low Energy (BLE) technology by adding direction finding capability

• Provides up to 0.3 m position accuracy

• Based on directional positioning beacons installed in covered areas

• Beacon density similar to WiFi access point density

• Typically 1 beacon / 100 - 2500 m2 depending on installation height

• No calibration required

• One way communication is sufficient between the mobile and the positioning beacon, i.e. time synchronization is not needed

• Mobile locates itself by measuring DoD (Direction of Departure) of a signal broadcasted by the positioning beacon

• No networking connection needed

• No latency

• No privacy concerns

6

Nokia Research Center

Localization Principle with a Single Positioning Beacon

x

y

f

q

hm

z

zm

xm

ym hm = 1.2-1.4 m

Using a single antenna and

fixed mobile height, mobile

can resolve its 2D location

TX / RX

RX / TX

TX: transmitter

RX: receiver

7

Nokia Research Center

Localization Principle with Multiple Positioning Beacons

x

f1

q1

z

zm

xm

ym

z\

x\

f2

q2 Using multiple positioning beacons,

mobile can resolve its 3D location

or increasing the position

reliability and accuracy

TX: transmitter

RX: receiver

TX / RX TX / RX

RX / TX

8

Nokia Research Center

System Configuration: Server-centric approach Asset tracking mode

BLE Tag

BLE phone

Global

Beacon

Database

Positioning

Server

Positioning Beacon

(in receive mode)

3GPP

WLAN

9

Nokia Research Center

System Components: Mobile-centric approach Mobile positioning mode

Positioning Beacon

(in broadcast mode)

Handset with Location

Enhanced BLE (LocBLE) onboard

Beacon

Database Bluetooth Low Energy (BLE)

2.4 GHz Broadcast

3GPP

WLAN

….

(network connection)

10

Nokia Research Center

HAIP Benefits

• Small power consumption

• Offers high accuracy; ~1 m in large open indoor areas and 0.3m in office space

• No calibration required

• No synchronization required

• Provides clearly better accuracy and reliability than fingerprinting based WiFi positioning technologies

• Specific to Server-Centric approach

Tags are small, cheap, and have low power consumption

Tags can be commanded to become active for real-time tracking

• Specific to Mobile-Centric approach

Beacons may be battery powered and standalone (no network connection required)

Allows unlimited number of mobiles to position themselves

No network dependence => no cost, no latency, no privacy concern

No additional HW required in the phone

11

Nokia Research Center

HAIP Experimental results

• Two positioning beacons mounted on ceiling at height of 20 m

• Positioning error < 0.5 m @ 50% and <1 m @ 90%

Real path

Measured path

Positioning Beacon X

12

Nokia Research Center

HAIP Demonstration: Skater tracking in an ice rink

13

Nokia Research Center

HAIP Technology Status

• Current prototypes are built by modifying the Bluetooth Low Energy standard

• Discussions initiated late 2010 about standardizing the technology as part of future versions of Bluetooth

• Recently submitted to BT SIG as standardization proposal

• Preparations going on to start standardization work

• Technical standardization work estimated to start during 2011

• Estimated availability of chipsets starting 2012/2013 onwards, presuming successful standardization

• Industry consortium under planning to support infrastructure ecosystem creation

• Verification of new business opportunities and creation of joint industry solution

• Pre-commercial pilots during 2011/2012 being planned by Nokia and Navteq

• No information currently available on product schedules

14

Nokia Research Center

Summary

• Satellite based positioning will not offer ubiquitous coverage indoors

• Cell-ID and WiFi network based positioning is already widely available but accuracy is limited to building level

• Turn-by-turn indoor navigation requires systems specifically designed for positioning purposes

• Nokia HAIP technology is built on BLE and offers sub-meter location accuracy indoors

• Standardization work currently taking off in BT SIG

• Products available earliest 2012-2013

• Pre-commercial pilots are being planned by Nokia and Navteq to start the ecosystem creation for indoor positioning systems

• Link to video demonstration of HAIP: http://research.nokia.com/news/9505

15

Nokia Research Center

Thank You

16