Most (cheap, commercial-grade) GPS’s won’t let you get at the raw satellite measurements. The Fastrax IT03 models will (at a programmable output rate!), and also allow you to tweak a bajillion other parameters through a comprehensive SDK. As near as I can tell, the only reseller that will offer the modules (IT03-S is the one I want) is based in the UK (m2m-online), selling for about 25 GBP. It would be really nice if SFE could act as a sample-quantity distributor in the US, possibly with your own dev board as well. Pretty please?
Any GPS module based on the SiRF chipset should allow you to get that data using SiRF’s ‘Binary Protocol’ http://www.MadeEasyKits.com/Docs/SiRF_B … otocol.pdf. I sell the Leadtek 9548S, that is based on that chipset. COntact me if you’d like to purchase some. I also have a break-out board available.
The SiRF III almost supports it. The binary protocol only includes the sample time and pseudorange, it doesn’t include the carrier phase info. See the GPSD hardware http://gpsd.berlios.de/hardware.html pages for more info. There have been reports of IT03 users cranking up the serial port baud rate up to just shy of 1Mbps with a raw measurement rate of 100 Hz (satellite pseudo-ranges only, no PVT fix calculation).
Neat, I’ve been looking for a GPS module exactly like this - but I can’t find that store. Can you link it?