This document introduces RAW GNSS measurements provided by the Android Nougat API. It discusses how the new API allows access to pseudoranges and carrier phase measurements directly from GNSS chips. This level of access was previously only available to GNSS experts and provides opportunities to improve positioning accuracy through sensor fusion and external corrections. The document also addresses challenges in working with the new API and limited hardware support currently from mobile chipset vendors.

1. Introduction to GNSS RAW measurements
provided by Android N
WhereCamp Berlin
Lukasz K Bonenberg
NGI, University of Nottingham
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2. RAW GNSS?
Figure 1: Android Nugat
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3. meaning?
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4. Existing API
Figure 2
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5. New Android Nugat API v24+
Figure 3
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6. A challenge
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7. It’s hardware stupid
Figure 4 7

8. GNSS experts only?
Figure 5: Pseudoranges
L =
Treceiver
arrival
− T
satellite
transmission
c
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9. 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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10. 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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11. 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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12. An opportunity
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13. 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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14. Other?
• mass market applications
• data collection & analysis
• position quality estimation
• data fusion
• . . .
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15. Live demo
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16. 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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17. Thank you
Lukasz.Bonenberg@nottingham.ac.uk
https://github.com/DfAC
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