Jeff Anderson wrote:
I'm curious how you adjusted phase - it seems to me this should be done with
an all-pass filter, but perhaps there are better/different techniques?
Could you describe what you did in more detail?
Jeff,
it is quite simple. If you visualize the analytic signal as a rotating
phasor, then the I and Q components are the projection of that signal on
the two orthogonal axis X and Y. Having a phase error means that the values
you have are the projections on two axis not perfectly orthogonal.
Without loss of generality suppose the Y axis is slightly tilted, so that
the projection of the Y vector on the X axis is not zero, but some small value.
If you combine vectorially the Y vector with this projection (with sign
changed),
you get what the value on the correct orthogonal Y axis should be. That's all.
Just some basic trigonometry.
73 Alberto I2PHD
