for one section of my project, i need to know the phase difference between two signal.(adsbygoogle = window.adsbygoogle || []).push({});

they are both 40MHz, but out of phase by a certain angle.

i have a AD8333 board from Analog Devices,

it is a dual I/Q demodulator consist of double-balanced gilbert cell mixers.

The board has 2 RF inputs, a LO input, and 4 output (I1, I2, Q1, Q2).

I have an oscilloscope to display the results.

according to wikipedia http://en.wikipedia.org/wiki/Phase_detector#Analog_phase_detector

there is a way to measure the phase difference using IQ demoludator.

in this post, https://www.physicsforums.com/showthread.php?t=336619

f95toli mentioned that:

the magnitude is just given by the norm (sqrt(I^2+Q^2)) and the phase by the phase angle (arctan I/Q)

So is this method bellow correct?

to get the phase difference of both my RF signal,

i put one the signal into RF input1, and the second signal into the LO,

then i display both the I1, and Q1 in the oscilloscope, and get an get the peak to peak magniture for both the I1 and Q1, then calculate arctan I1/Q1, to get the phase difference?

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# How to measure phase difference of 2 signals using IQ demodulator

Can you offer guidance or do you also need help?

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