Definition - What does Phase Shift mean?
Phase shift is a common term in the study of waveforms and communication of signals. It refers to the displacement of two signals when propagated in a time domain. This displacement can be caused by a signal processing device such as an electronic amplifier or a low- or high-pass filter that performs certain operations on the signal, causing the output signal phase to shift from its original input signal phase.
Phase shift is also known as phase change.
Techopedia explains Phase Shift
It is important to understand that phase shift does not change the frequency of the signal. Two signals having a phase shift may or may not be of the same frequency. Phase shift simply means that the two signals are at different points of their cycle at a given time. Phase shift is measured as the angle (in degrees or radians) between two points on a circle at the same time, demonstrating the progress of each wave through its cycle. Phase shift is more easily observed in sine waves where there is a single fundamental frequency and no harmonics.