The Hilbert transform is a linear operation used in telecommunications engineering to obtain spectrally efficient signals. It translates signals into a phase shift of -90º at positive frequencies and +90º at negative frequencies. In the frequency domain, the Hilbert transform results in a phase shift of 90°. The Hilbert transform can be applied to baseband and bandpass signals, resulting in phase distortion in the time domain. However, in the case of bandpass signals, the envelope of the transformed signal remains the same as the original signal, making it suitable for communication without distortion. The Hilbert transform is used in applications such as single sideband spectrum (SSB) and the generation of quadrature signals.
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