Fig. 7: The TPC sequences and spectral intensity of harmonics.

The TPC sequences of \({\varphi }_{{xx}}^{{\rm{RPM}}}\)(t) and \({\varphi }_{{yy}}^{{\rm{RPM}}}\)(t) (upper panel), their corresponding ∆φ(t) and β(t) (middle panel), as well as their corresponding theoretical and measured spectral intensity of harmonics (bottom panel) for the (a) 0°-, (b) 45°-, and (c) 90°-polarized reflection waves, where the length of the TPC sequence is L = 4, and modulation frequency is f0 = 100 kHz. The solid lines and the dashed lines indicate the simulated and measured results, respectively