Neo FreeRunner GPS Software Fix Test Report

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See [[GPS_Problems]] for details on Freerunner GPS problems.
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See [[GPS_Problems]] for details on FreeRunner GPS problems.
  
=== Problem: it takes a long time (10min+) before the Freerunner gets first GPS data ===
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=== Problem: it takes a long time (10min+) before the FreeRunner gets first GPS data ===
  
 
It was found that the Openmoko FreeRunner GPS has a long Time To First Fix (TTFF) with the SD card in the phone. [http://lists.openmoko.org/pipermail/community/2008-July/021774.html This thread] indicates that there is interference from the SD card slot, as without the SD card inserted it the TTFF are much shorter.
 
It was found that the Openmoko FreeRunner GPS has a long Time To First Fix (TTFF) with the SD card in the phone. [http://lists.openmoko.org/pipermail/community/2008-July/021774.html This thread] indicates that there is interference from the SD card slot, as without the SD card inserted it the TTFF are much shorter.
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[[Category:GPS]]
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[[Category:Neo FreeRunner solved GPS problems]]
[[Category:Neo FreeRunner Hardware]]
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Latest revision as of 11:36, 18 July 2009

See GPS_Problems for details on FreeRunner GPS problems.

Contents

[edit] Problem: it takes a long time (10min+) before the FreeRunner gets first GPS data

It was found that the Openmoko FreeRunner GPS has a long Time To First Fix (TTFF) with the SD card in the phone. This thread indicates that there is interference from the SD card slot, as without the SD card inserted it the TTFF are much shorter.

More specific: the GPS signal level drops by -20dBm, i.e. factor 100. Signal strength of a GPS satellite above your head is around -127dBm. Needed strength for a first fix is -145dBm with a minimum of three satellites. Once the GPS chip has a fix, it can operate at signal levels of -157dBm, thus making it possible to operate while there is data transfer from/to the SD card.
(From http://lists.openmoko.org/pipermail/community/2008-July/022202.html )

[edit] Test Enviroment

[edit] Test Script


[edit] Test Result

|- | Date || Location || Image used |-

Personal tools

See GPS_Problems for details on Freerunner GPS problems.

Problem: it takes a long time (10min+) before the Freerunner gets first GPS data

It was found that the Openmoko FreeRunner GPS has a long Time To First Fix (TTFF) with the SD card in the phone. This thread indicates that there is interference from the SD card slot, as without the SD card inserted it the TTFF are much shorter.

More specific: the GPS signal level drops by -20dBm, i.e. factor 100. Signal strength of a GPS satellite above your head is around -127dBm. Needed strength for a first fix is -145dBm with a minimum of three satellites. Once the GPS chip has a fix, it can operate at signal levels of -157dBm, thus making it possible to operate while there is data transfer from/to the SD card.
(From http://lists.openmoko.org/pipermail/community/2008-July/022202.html )

Test Enviroment

Test Script


Test Result

|- | Date || Location || Image used |-