expect to sub-contract the design work but looking for an opinion first about practicality.
range, and report their relative phase with at least 50 nsec accuracy.
advance and are assumed to be perfectly stable. Nominal C/No >50 dB/Hz each carrier.
want to know is how much one leads or lags the other in time, like measuring the relative zero-crossing times of the two sinusoids. For measurement accuracy it is acceptable to time-average each measurement over as long as 100 msec.
assuming this concept is practical. Any recommendations for someone to do the design are appreciated. We are located in Southern Calif.
curve fit of the difference tone amplitude against time? How do we get relative phase of the two RF carriers from the curve fit?
And there is never enough of either. Sometimes I wish the day would have
30h, and I bet the FCC wished that UHF had another dozen or so 100MHz slivers they could hock for a ton of money :-)Nowadays we can say it's easy to measure but that was different when we were young. Back then the only way to measure frequency (somewhat) precisely was to beat it with known signals, hoping the radio stations were tuned well. Which was sometimes a dicey bet. Same with time, the most precise instrument we had was our grandparent's regulator clock. Then at age 18 or so I had enough dough from my army pay that I could buy a 1MHz crystal and some TTL chips to build a more precise timing device.