> If you do not limit yourself to NMEA you can get L1/L2 C/A and P-code and > both code and carrier phase in rates higher than 1 Hz. I have such > receivers, and you can get them as modules.
NMEA was designed for boat navagation and works well for that. I don't need NMEA for timing. What can I look for that is in the About $100 range and can receive L2. > From one second to the other, you usually do not change speed or direction > that much. Your typical receiver will produce both position and velocity > vector, so Kalman filtering on that isn't too hard. In a car you can be out of GPS coverage for a long time. Tunnels and parking structures are obvious but also tall buildings on both sides of a street and even trees. You could be out of GPS for many minutes at a time so odometers, compass and gyros are helpful. On my sailboat autopilot the GPS was supplemented by a compass, water speed sensor and gyro because GPS knows only position and not orientation. Chris Albertson Redondo Beach, California _______________________________________________ time-nuts mailing list -- [email protected] To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts and follow the instructions there.
