Difference between revisions of "GPS receiver testing"
(aww shit this is gonna be fun)
Revision as of 00:01, 26 October 2012
For the balloon and other projects, it's good to know before flight that your GPS receiver will work as you expect it to. Unfortunately, it's difficult to do repeatable testing with a signal that varies in quality and availability. It's even more difficult when you're unable to physically get to 60,000' of altitude, where you want to confirm the unit's behavior!
Enter the LabSat. LabSat is a GPS signal simulator. Think of it as a "sound-card" for GPS L1 RF. You can record a "wav file" of GPS signal, then play it back as many times as you want, say, into different receivers, and see how they behave. With the accompanying SatGen software, you can synthesize arbitrary scenarios, and play those too. This all happens at the radio level, so you might want to put the GPS receiver into an RF chamber so it hears only the LabSat and not the real signals.
But surely those must be expensive!
Yes, yes they are. There doesn't appear to be a DIY SDR GPS RF generator project yet, so for the time being, we're gonna borrow a LabSat. It's being provided by VBOX USA, the North American dealer for LabSat products.
This page is to coordinate the procurement of receivers to test, the generation of scenarios to try, the gathering of results, and the return of receivers once testing is completed.
|Receiver name||Physically have it?||Chipset||Firmware||Protocols to test||Ready to test?||Return to...|
|Lassen SQ||Yes, e-room GPS bin||unknown||unknown||NMEA and TSIP||no! Needs breakout board, 3v3 reg, ant.||n/a, we own it.|
|ublox NEO-7||nope, just wishlisting||ublox 7||unknown||NMEA and UBX||no, have to acquire first...||the kind soul who supplies one!|
|Scenario name||Written by||Link to script||Generated? Delivered?|
|Progressive jerk squares||maybe Nate B||not yet||no, no|