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--- mission:log:2011:09:27:gps-modules-devkits-generously-provided-by-ublox [2012-02-16 12:41] – chrono
+++ mission:log:2011:09:27:gps-modules-devkits-generously-provided-by-ublox [2013-06-05 14:34] (current) – external edit 127.0.0.1
@@ Line 1: / Line 1: @@
+====== GPS Modules & DevKits generously provided by uBlox ======
+Even the earliest Apollo-NG design drafts already included multiple GPS dependencies for a number of subsystems. Apart from obvious navigation assistance, GPS will also discipline the reference clock module and the 10MHz reference oscillator module [[lab:resources:GPSDO]]. The first prototype was hacked around an old Rockwell/Connexant Jupiter TU30-420-031 GPS receiver, found on eBay.
+===== =====
+Unfortunately, this module is relatively old, consumes too much power and it's hard to get a replacement module in case of failure. It only supports 10 channels, speaks a very narrow Zodiac Binary protocol, NMEA is almost unusable and it only offers 10kHz sync output, making a frequency divider neccessary in order to drive the PLL of the GPSDO. After a lot of work on #gpsd and some kernel hacking to get Kernel-PPS support on ARM,  the reference clock worked reasonably well (UTC Offset: 17 nanoseconds avg):
+[{{:mission:log:2011-09-27:jupiter_chrony_time_offset_utc.png?295|Ref. Time-Offset to UTC}}]
+[{{:mission:log:2011-09-27:jupiter_gps_visible_sats.png?295|GPS - Visible Sats}}]
+After evaluating many GPS chips, uBlox's LEA-6 series seemed to be top notch, in every aspect:
+  * 50 channel receiver
+  * -162dB tracking sensitivity
+  * WAAS/EGNOS/GALILEO/GLONASS support
+  * 10MHz sync output
+  * Dead-Reckoning features (LEA-6R)
+  * Precision-Timing features (LEA-6T)
+  * gpsd offers great ublox binary support now
+Gitte Jensen, Corporate Communications Manager for uBlox, understood the Apollo-NG concept directly and went all the way, not only sponsoring just a GPS chip, but 4 GPS Modules (2x LEA-6T + 2x LEA-6R) AND the matching Development Kits as well. The Odyssey can now fly with a high-end GPS setup, employing active fail-over redundancy. If one GPS module should fail, the other can take over the sibling's dependencies with a slight decrease in specific use-case precision. So, all you boys, girls & gender-neutral beings, interested in GPS technology and uBlox implementations, now you can just take the DevKit and directly start to plug & play. uBlox should be grateful, to have such a far-sighted Corporate Communications Manager who does a great job, representing a company, that tries to fulfill its social responsibility by taking care of future engineers and young enthusiasts.
+<blockquote>The reason why I am interested is, that we, within our CSR program, strive to enlighten young people to the exciting world of engineering.<cite> Gitte Jensen, uBlox Corporate Communications Manager</cite></blockquote>
+Thanks a lot to uBlox and big hugs to Gitte, for her great support.
+{{tag>gps sponsor ublox lea-6 sku gpsdo odyssey research}}
+~~DISCUSSION~~

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