A Look-up Table Based Digital Predistortion Technique with Iterative Usage of Feedback Samples

A new digital predistortion (DPD) method based on lookup table (LUT) is proposed for linearizing power amplifiers (PA). LUT and Polynomial based DPDs are two popular DPD techniques. Between them, LUT-based DPD is simpler to implement, but it needs longer convergence time than the polynomial DPD, and longer feedback samples are required. As a result, the LUT-based DPD techniques need large memory for storing long feedback and transmit samples. This requirement increases hardware complexity and cost due to the large memory. To overcome this problem, we propose a new LUT-based DPD technique that iteratively utilizes a short feedback and transmit samples. Experimental results show that the proposed technique can linearize the nonlinear PA with only 30 times shorter feedback samples than the conventional LUT-based DPD techniques.