# Imaginary and real parts of interferometry

Hello all

I had calculated the phase interferometry from and it works very good.

my question is how snap calculate the imaginary and real parts.
the ones used for the phase calculation are showed in the figure.
i_ifg_VV_07Nov2017_19Nov2017
q_ifg_VV_07Nov2017_19Nov2017

The master image= (i & q)_master is multiplied pixel-wise with the complex conjugate of the slave= (i & -q)_slave so that you end up with the interferogram= (i & q)_interferogram.

Thank you, but I mean how to calculate i_ifg_VV_07Nov2017_19Nov2017

for example this case

As I wrote above - i and q are the real and imaginary parts of a complex number so vector multiplication is involved.

if you want to compute it “manually” via “band maths” for example, remember that the interferometric phase is given by

where m is the master image, s is the slave (both complex numbers) and * designate the conjugate. Expanding the expression of the hadamart product, we have

Then you can compute the interferometric phase

Hope it helps.

Note that this expression does not remove the orbital phase, given by

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