International audienceAn improved baseband Digital PreDistortion (DPD) solution to reduce the nonlinearity of Power Amplifiers (PAs) with memory effects is proposed. It is based on the Memory Polynomial (MP) model and linearly interpolated Look-Up Table (LUT). This predistorter reduces significantly the computational time needed in MP based DPD by using a LUT. A linear interpolation technique is introduced to enhance the indexing of LUT, such that good performance with small table size and low computational complexity is achieved. The proposed solution is validated on a test bench using a PA ZFL-2500 driven by a 16QAM modulated signal

A new digital predistortion technique based on a direct learning architecture is proposed for linearising power amplifiers (PAs) with nonlinear memory effects. It is based on the non-uniform memory polynomial (MP) model and with a quadratically interpolated LUT. There are mainly two innovations. First, compared with the conventional MP model, the non-uniform MP model achieves the same modelling accuracy with less coefficients. Secondly, compared with the linearly interpolated LUT, the quadratically interpolated LUT has higher accuracy, which is adopted to realise a part of the mathematical computations in the predistortion. The proposed solution is validated on a real PA ZFL-2500. It reduces the number of the model's coefficients and achieves a spectrum regrowth suppression of about 15 dB with a table size of only 8.