Wednesday, March 19, 2008
Forward Linear Prediction
The digital resolution in an NMR spectrum can be improved by zero filling the FID (i.e. adding zeros to the end of the FID before Fourier transformation). Forward linear prediction, on the other hand, can be used to improve both the digital and real resolution in a spectrum. Forward linear prediction uses the data collected in an FID to predict data after the receiver was turned off. Both processing techniques artificially increase the acquisition time, however it is only forward linear prediction which adds new information to the spectrum. In the figure below a truncated FID is transformed untreated, with zero filling and with forward linear prediction.