DATA REFLECTION ALGORITHM FOR SPECTRAL ENHANCEMENT IN FOURIER-TRANSFORM ICR AND NMR SPECTROSCOPIES

The use of a data reflection algorithm in which the signal acquired in real time is juxtaposed with the same signal reflected relatively to zero time axis through exact phase matching is considered. Because of the additional information provided by a knowledge of the exact initial phase of the signal, the resulting Fourier transform (FT) spectra have a higher resolution and signal-to-noise ratio. This algorithm was applied to ion cyclotron resonance and nuclear magnetic resonance time-domain signals. In both cases, the method improved the FT spectra compared with the original ones. It was found that artifacts may result from the time delay between the end of the excitation event and the beginning of the acquisition period, as web as from time-dependent excitation wave forms such as chirp excitation. Possible ways to decrease or eliminate the artifacts are considered. Comparison to other spectral enhancement techniques is made.