Introduction to GNSS RAW measurements provided by Android N

Introduction to GNSS RAW measurementsprovided by Android NWhereCamp Berlin

Lukasz K Bonenberg

NGI, University of Nottingham

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RAW GNSS?

Figure 1: Android Nugat

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meaning?

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Existing API

Figure 2

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New Android Nugat API v24+

Figure 3

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A challenge

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It’s hardware stupid

Figure 4 7

GNSS experts only?

Figure 5: Pseudoranges

L =T receiver

arrival− T

satellitetransmission

c8

Mass market?

• Limited hardware at this stage1

• hardware forced to comply from mid 2017

• No battery drain but..• Duty cycle - problem with clocks

• many producers, many implementation• market coverage?

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• Qualcomm Snapdragon 650, 820• Broadcom BCM4774• Intel WCS2x00

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Help is here

Google released Matlab code showing:

• example logger application• the details of obtaining pseudoragnes• calculating position

I work on python version

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What about API

• most devs focus in high abstraction - gms.location• for RAW measurements use android.location

• not so easy to use• check Matlab code for implementation details

• google . . .

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An opportunity

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Improved position

• using external corrections (DGPS)• reduce errors in urban areas (GNSS shadowing)• use sensor fusion• use carrier phase measurements?• improving on antenna ?

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Other?

• mass market applications• data collection & analysis• position quality estimation

• data fusion• . . .

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Live demo

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Useful links

• Google code• my gitHub with python code• my gitHub with edits to google code• Simon Banville blog• Rokybun blog

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Thank you

Lukasz.Bonenberg@nottingham.ac.uk

https://github.com/DfAC

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