Hammerstein predistorter for high power RF amplifiers in OFDM transmitters

OFDM (Orthogonal Frequency-Division Multiplexing) is a wideband digital modulation scheme which is critically dependent on linearity in the hardware system, due to its reliance on Fourier Transformation and its inherently high peak-to-average power ratio (PAPR), and minimization of nonlinearity is thus a priority. In this paper the effectiveness of a predistortion based on the Hammerstein model dealing with the nonlinear response is investigated by measurement of Error Vector Magnitude (EVM) in AWGN channel and Adjacent Channel Power Ratio (ACPR). Accuracy of prediction of Power Amplifier (PA) nonlinearity with memory effect and baseband predistorter is investigated by the experimental results.