Novel Pre-Distortion of Power Amplifier with Proposed Fractional Order Memory Polynomial

In this paper, we propose two novel schemes, which are based on our proposed novel fractional order memory polynomial pre-distorter, to conduct the digital base-band power amplifier pre-distortion with the improvement of power amplifier efficiency. For the first scheme, fractional order terms are included in the conventional memory polynomial containing the odd and even order polynomial terms. For the second scheme, it is to replace even order polynomial terms with fractional order polynomial terms to improve the linear performance of power amplifiers. The theoretical expressions for two schemes are derived. Both simulation results and numerical analysis show that more 11.0dB and 8.5dB out-of-band suppression gain could be obtained employing the proposed two schemes, respectively, which are compared with the conventional pre-distortion methods based on Wiener-Hammerstein and memory polynomial power amplifier models. Moreover, corresponding FPGA realization shows that the proposed two schemes are much cost-effective in terms of hardware resources and complexity of the implementation is low.