Low-Power, Long-Range, Precise Localization

Low-Power, Long-Range, PreciseLocalization

Nextech 2014, Rome - 28 August 2014

Prof. Maarten [email protected]

Maarten WeynResearch:

I Localization: from Opportunistic to Just Enough

I Low-power communication

I Low-power firmware development

I Simultaneous Localization and Mapping

Courses:

I Mobile Communication

I Digital Communication

I Real-Time Localization Systems (Eng)

I Ambient Intelligence (Eng): interaction between low-powercommunication, sensors, actuators, low-power hardware andalgorithms

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What I’m not going to do...

I No sales talk

I No academic formula’s and equations

I No futuristic foresights

I No ”You should’s”

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Low-Power, Long-Range, Precise Localization

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PowerBudget

Range

Accuracy/Precision

Responsiveness

Tag Size

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PowerBudget

Range

Accuracy/Precision

Responsiveness

Tag Size

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PowerBudget

Range

Accuracy/Precision

Responsiveness

Tag Size

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Power Budget

Low Power?:

I LG Nexus 5: 2300 mAh / day ?!!!

I Raspberry pi: 500 mAh

I TelosB

Application Driven:

I e.g.: 1 year on coin cell (220 mAh)

I e.g.: ”the lifetime of the bird andweight ≤ 1 gram”

I e.g.: 2 year on 1/2 AA 3.6V battery(1100 mAh) → 62µAh/day

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Power Budget

Low Power?:

I LG Nexus 5: 2300 mAh / day ?!!!

I Raspberry pi: 500 mAh

I TelosB

Application Driven:

I e.g.: 1 year on coin cell (220 mAh)

I e.g.: ”the lifetime of the bird andweight ≤ 1 gram”

I e.g.: 2 year on 1/2 AA 3.6V battery(1100 mAh) → 62µAh/day

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Power Consumption: e.g. BLE

I 3 x 12.8 mA x 660 µs (0dBm)

I 0.00704 µAh / beacon

I iBeacon: 10 msg/s

I → 253.44 µAh

→ ± 1 month with a coincell battery

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Power Consumption: e.g. BLE

I 3 x 12.8 mA x 660 µs (0dBm)

I 0.00704 µAh / beacon

I iBeacon: 10 msg/s

I → 253.44 µAh

→ ± 1 month with a coincell battery

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Accuracy vs Precision

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Accuracy vs Precision

Source: Versus Technology, Inc.

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Range

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Range

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Range

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Techniques

I Signal Strength:I AttenuationI Pattern Matching (Fingerprinting)I Presence / Proximity

I Time (Ranging):I Time of Flight - Time Difference of ArrivalI Round Trip Time

I Direction Finding / Angle of Arrival

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Signal Strength

RSSd = PrdBm = 10 logPr (d0)− 10np logd

d0+ X

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Attenuation

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Attenuation

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Attenuation

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Pattern Matching

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Presence Detection

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Time of Flight: Time Difference of Arrival

TDOAB-A

TDOAC-A

A B

C

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Time of Flight: Round Trip Time

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Time of Flight: Cramer Rao Bound

σ2r̂ ≥c2

4π2B2EsN0

Source: Lanzisera et al.: Radio Frequency Time-of-Flight Distance Measurement

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Direction Finding

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Direction Finding

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PowerBudget

Range

Accuracy/Precision

Responsiveness

Tag Size

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DASH7

Active RFID Standard for 433 MHz.

I Build on top of asynchronous WSN MAC.

I High level functionality optimized for RFID.

I Defines full functional RFID tag.

I Can be extended to non RFID applications.

Supports Tag to Tag communication.DASH7 Alliance Protocol is designed to support fixed and mobilenodes that need to upload or retrieve small chunks of information

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DASH7

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DASH7

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DASH7

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Open Source Stack for DASH7

http://oss-7.cosys.beLGPL v2.1

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Open Source Stack for DASH7

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Localization Benchmarking

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RF-based Ratlsam

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Questions?

[email protected]

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