Modeling of OFDM Systems With Memory Polynomial Power Amplifiers

Nonlinear power amplifiers (PA) are often modeled as a memoryless polynomial. However, when the input signal bandwidth is large, PA memory effects can not be ignored. The memory polynomial model is a simple but efficient model that captures both memory effects and nonlinear behavior of a PA. In this work, a new theoretical result concerning orthogonal frequency division multiplexing (OFDM) systems with a memory polynomial PA is demonstrated. It states that such an OFDM system can be expressed as a OFDM system with a memoryless polynomial PA whose coefficients vary from one subcarrier to another.