Title :
A Blind AM/PM Estimation Method for Power Amplifier Linearization
Author :
Zhiwen Zhu ; Xinping Huang ; Caron, Michel ; Leung, Henry
Author_Institution :
Commun. Res. Centre Canada, Ottawa, ON, Canada
Abstract :
A higher order statistics (HOS)-based method is proposed in this letter to estimate the nonlinear amplitude-to-phase (AM/PM) conversion function of power amplifiers (PAs) in communications systems. By utilizing the symmetry property of the modulated signal, the proposed method estimates the AM/PM conversion function using only the PA output signal, from which the phase predistorter (PD) function can be derived. Simulation results show that the HOS-based method can accurately determine the phase PD function required to compensate for the AM/PM distortion in the PA, yielding a linearization performance close to that of non-blind methods in terms of adjacent channel power ratio and error vector magnitude.
Keywords :
higher order statistics; nonlinear estimation; power amplifiers; AM-PM conversion function; AM-PM distortion; HOS-based method; PA; PD function; adjacent channel power ratio; blind AM-PM estimation method; error vector magnitude; higher-order statistics; linearization performance; modulated signal symmetry property; nonlinear amplitude-to-phase conversion function; phase PD function; phase predistorter function; power amplifier linearization; Constellation diagram; Estimation; Nonlinear distortion; Pulse shaping methods; Standards; Timing; Vectors; AM/PM conversion; Power amplifier; higher order statistics; nonlinear; predistorter;
Journal_Title :
Signal Processing Letters, IEEE
DOI :
10.1109/LSP.2013.2280394
