INPUT NYQUIST SAMPLING SUFFICES TO IDENTIFY AND COMPENSATE NONLINEAR-SYSTEMS

Nonlinear systems usually cause spectral spreading resulting in an out put signal bandwidth greater than that of the input signal. When ident ifying and compensating nonlinear systems by digital methods, it has b een common practice to set the sampling frequency at the Nyquist rate of the output signal. This correspondence presents experimental eviden ce for the author's proposal that nonlinear systems can be identified and compensated at the lowest possible sampling rate: the Nyquist rate of the input signal.