use of hilbert transform
a hilbert transformer is one which multiplies the input with a 'j' in the frequency domain. therefore it is used as a 90 deg phase shifter or in short a differentiator. thus we can use them wherever a differentiator is needed. however, it is very difficult to build one. in quadrature amplitude multiplexing, costas receivers and quite a few applications we need to use a 90 deg phase shifter.
regards,
also refer this site..
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