DESIGN AND ASSESSMENT OF SYMMETRICAL PHASE-SHIFTING ALGORITHMS

Conventional phase-shifting algorithms based on a least-squares estimate use N samples over an incomplete period of the sampled waveform. We introduce a class of phase-shifting algorithms having N + 1 samples symmetrically disposed over one full period of the sampled waveform. Fourier analysis techniques are used to derive these algorithms and modify them to improve their performance in the presence of phase-shift errors. The algorithms can be used in phase measurement systems having periodic, but not necessarily sinusoidal, waveforms.