What is the fastest GPS module available?
Have you looked at the velocity limitations of commercial grade GPS Receivers? I'm under the impression that they won't report speeds greater than 600 Mph or so. @ 600 miles per hour, an update rate of 5 Hz gives you a point seperation of 176 ft (53 meters).
Dave
I'm not planning on moving at those speeds, so that's not really going to be any problem.
I just found the JNS100. Sigh. S2950... That is 100Hz without interpolation.. enough to supply a pretty decent Kalman filter with GPS measurements every Kalman update. Darn, now that's what I call high end electronics. Can't wait till these comes cheaper.
Edit:
to answer your question, some of the GPS unit's I've seen lately carries the note "Almost unlimited altitude and velocity (for authorized users)"
This isn't relevant to your report rate question, but there are limits to GPS speed and altitude. The limit is 1000 knts and 60000 ft. You can exceed one but not both without an exception from the US Govt.
I seem to come across several P-code units on the net, these are the ones using the protected P(Y) key decryptor as far as I've gathered.. Are these restricted in sale, or can normal people and businesses buy them? do they have the Y-code programmed in or do you need to get it programmed by authorized personel?
I've never used the P-code, but as I understand it, the precision GPS code (P-code) is sometimes encrypted by a secret binary code (A code). The key word is "sometimes". As far as I know the military are the only ones with access when encrypted. The new military units are also getting equiped with a module known as SAASM (Selective Availability Anti-Spoofing Module) to help prevent use of military GPS receivers by unauthorized personnel. With all this in mind, I think that it would be a rare case to get an encrypted P-code receiver.
The C/A-code is a relatively short code which repeats every millisecond, where the P-code segment is one week long. Some of the earlier P-code receivers relied on the C/A-code to lock in first and then switch to P-code.
Ive been looking for the same thing but in chipset form, no luck yet.