Is it established that the 0x8F-AC and A7, 10 MHz and PPS offset measurements are not the output from some internal filter estimation? It would be interesting to relate the 0x5A individual doppler measurements to the individual 0x8F-A7 SV clock biases.

I need to find it because there were estimates of how long each part of the system calculations took to justify that the scheme would work.

The one relative effect which they maybe didn't account for is the Sagnac effect, which Tom estimated being about 2.3 ns which matches the difference found in the time-difference testing. This effect comes from the spinning of the earth.

Trimble Thunderbolt), or by using independent clocks and estimating the resulting quantization error (most timing-oriented receiver-only modules). In a from-scratch design I don't think there's any reason not to use the disciplined clock, but there could be lurking correlation problems.

Its generally quicker and cheaper to estimate the magnitude of such effects and make appropriate choices than just build a sequence of breadboards each of which then needs to be extensively characterised. Bruce Chris Albertson wrote: > You all are "inventing problem". Solve them AFTER you find a problem you > can measure.

I would recommend determining your terrain's elevation using a topo map and estimating or measuring antennas height above ground. And then excluding survey results with wacko altitudes before averaging.

>Is it possible to estimate the opamp's phase noise at a specific frequency >(say a sinusoid at 10MHz or 100MHz) from these curves? No, not really, because: >I'm assuming it can be seen as amplitude noise that is converted to phase >noise. Correct.

The frequency estimation process is not compatible with ADEV. > I tried to use the Dual Mixer Time Difference but the Phase Wrap is very difficult to manage during the measurements On a reasonably stable device with a rational beat note that should not be a problem.

It also produces frequency and ROCOF (Rate of Change of Frequency) according to standardized estimators. The phasor is normalized to that of the reference time and the frequency (50 or 60 Hz) setting. Phasor measurements up to 120 Hz is seen in installations, typically on voltages of all three phases, but also currents and sometimes on both.

Bottom line: If your estimates are within a foot of being correct, that’s probably good enough. Looking at the raw data is *always* a good idea.