DavidKelleySCSC
commented
3 years ago Could you provide the RTKLIB setting file as well. In the absence of more details... The default best guess is that uBlox got to see the Doppler measurements (in UBX message content) while RTKLIB did not (not clear if it was fed UBX or RTCM). RTKLIB will use Doppler when present, but it is only found in RTCM MSM types 6 and 7 (but is present in UBX). Since your fix rate is so low, you might want to try again with the mode set as static. One would expect an increased fixing rate under your conditions. No change would imply something else is at fault here. You do not state if the fix, once obtained, was kept or if this was an up/down sort event, also tell us the baseline distance.
raw data(~40min,time tagged) : Compare_Fail.zip L1.log->Rover L2.log->Base
configurations: uses a NEO-M8P receiver configured with 5Hz refresh rate,raw data output (SFRBX & RAWX enabled),GPS+Compass GNSS L1/B1 signal enabled. NEO-M8P was connected to PC via USB. uses an antenna mounted on rooftop with no high building in sight. RTKLIB Version 2.4.2 p13,with all configurations default except for :
EXPERIMENT: the SAME rtcm3 basestation data was provided to RTKLIB & NEO-M8P simultaneously. NEO-M8P got a lock after ~5min and keeps a stable fix, but RTKLIB lost FIX after ~8min and get only ~30% FIX rate .
Why?