Hi,
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For example
Are sin(2Πfct) and sin(2Πfct) orthogonal for one period?
Is this possible?
Does that have mathematical expression?
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My understanding about orthogonal is as: If the dot product of two vectors (or signals) is equal to zero, then they are orthogonal. This is very fundamental check on orthogonality. In your example, I dont think that these two signals (provided that they are equal in all respects) can be orthogonal. You can get orthogonal projection of one signal on anohter by using Gram-Schmidt transformation, Householder Transformation, or Givens Transofrmations.
In some sense orthogonality is realted to Correlation as well. So if two signals are orthogonal, then they will be somehow un-correlated, but this is very loose check, because Correlation has some other meanings as well. But for your example as signals are correlated so they eventually cant be orthogonal.
I hope I made my point.
BR,
Arif Kan
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