Re: [Discuss-gnuradio] Using DSP for precise zero crossing measurement?

[Johnathan Corgan]

John Ackermann N8UR wrote:

> The zero crossings are then used to calculate the time interval (or
> phase) between the two waves.  I need to capture each pair of zero
> crossings, and can't average over multiple intervals.

If it is the phase difference that you are ultimately looking for, there
are alternatives to measuring the zero crossing difference in the time
domain.

How precisely are the two sine waves matched in frequency?  How hard
would it be to come up with reference waveform representing "zero"
phase? How often do you need to measure the difference?

-Johnathan