TY - JOUR
T1 - Digital predistortion for concurrent dual-band transmitter using a 2D-LUT based Hammerstein architecture
AU - Cheng, Sheng Lung
AU - Wu, Wen-Rong
AU - Peng, Chun Hsien
AU - Liu, Jen Yang
AU - Hsu, Chen Jui
AU - Liang, Paul
PY - 2017/1/1
Y1 - 2017/1/1
N2 - Digital predistortion has been proved to be an effective remedy for the nonlinear distortion in radio-frequency power amplifier. Unfortunately, conventional digital predistorters (DPDs) developed for single-band transmitters can not be directly applied to concurrent dual-band. To solve the problem, DPDs with two dimensional memory polynomials were then proposed. Although they can provide good performance, its computational complexity is high for the estimation of polynomial coefficients. Look-up-table (LUT) based DPDs, developed for single-band transmitters, can effectively solve the problem. However, there are limited studies about LUT based DPDs for concurrent dual-band transmitters. In this paper, we propose a two-dimensional LUT based Hammerstein DPD to solve the problem. Analyzing the signals on both bands, we propose a new adaptive algorithm with the gradient-descent and recursive-least-squares (RLS) methods to train the DPD iteratively. With the proposed method, the computational complexity in the identification of the DPDs can be significantly reduced. Finally, simulations and experiments are conducted to demonstrate that the performance of the proposed DPD is comparable to that of the polynomial based DPD.
AB - Digital predistortion has been proved to be an effective remedy for the nonlinear distortion in radio-frequency power amplifier. Unfortunately, conventional digital predistorters (DPDs) developed for single-band transmitters can not be directly applied to concurrent dual-band. To solve the problem, DPDs with two dimensional memory polynomials were then proposed. Although they can provide good performance, its computational complexity is high for the estimation of polynomial coefficients. Look-up-table (LUT) based DPDs, developed for single-band transmitters, can effectively solve the problem. However, there are limited studies about LUT based DPDs for concurrent dual-band transmitters. In this paper, we propose a two-dimensional LUT based Hammerstein DPD to solve the problem. Analyzing the signals on both bands, we propose a new adaptive algorithm with the gradient-descent and recursive-least-squares (RLS) methods to train the DPD iteratively. With the proposed method, the computational complexity in the identification of the DPDs can be significantly reduced. Finally, simulations and experiments are conducted to demonstrate that the performance of the proposed DPD is comparable to that of the polynomial based DPD.
KW - Digital predistortion (DPD)
KW - Dual-band transmitter
KW - Hammerstein
KW - Look-up table (LUT)
UR - http://www.scopus.com/inward/record.url?scp=84997839783&partnerID=8YFLogxK
U2 - 10.1007/s10470-016-0893-z
DO - 10.1007/s10470-016-0893-z
M3 - Article
AN - SCOPUS:84997839783
SN - 0925-1030
VL - 90
SP - 125
EP - 136
JO - Analog Integrated Circuits and Signal Processing
JF - Analog Integrated Circuits and Signal Processing
IS - 1
ER -