Abstract
In this paper, we propose a new complex-type wavelet which we call RI-Spline wavelet. We show that the RI-Spline wavelet satisfies the admissibility condition and bi-orthogonal condition. That is, the RI-Spline wavelet can be used for continuous and discrete wavelet transform as the mother wavelet. As an application of the RI-Spline wavelet, we examine the relationship between the sound and vibration signals produced by golf club head impact, and analyze characteristic of unsteady turbulence. Our results demonstrate the advantages of our approach and show that the RI-Spline wavelet is effective for nonstationary signal analysis.