GNSSResearch » History » Version 1
dl lud, 06/24/2024 06:45 PM
First version with details about A-GNSS
| 1 | 1 | dl lud | h1. GNSS Research |
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| 3 | Research into Global Navigation Satellite Systems (GNSS) and related technologies. |
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| 4 | Example GNSS: GPS, GLONASS, Galileo, BeiDou. |
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| 6 | h2. Assisted GNSS (A-GNSS) |
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| 8 | Also known as Assisted GPS (A-GPS). Greatly improves the Time To First Fix (TTFF) by downloading almanac and ephemeris data via mobile broadband or WiFi, instead of waiting for the slow download via the GNSS signal. |
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| 10 | h3. SUPL |
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| 12 | SUPL (Secure User Plane Location) is the most common protocol used to retrieve almanac data. |
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| 13 | There are no free software SUPL servers that we know off. Android uses Google's servers (@supl.google.com@) by default. Most carriers also default to @supl.google.com@ on their APN. GrapheneOS runs a proxy at @supl.grapheneos.org@. |
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| 15 | h3. PSDS |
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| 17 | PSDS (Predicted Satellite Data Service). |