A new form of polynomial model for concurrent dual-band digital predistortion

This paper proposes a new form of polynomial model for concurrent dual-band digital predistortion. Different with usual 2D-DPD models, the new model introduces (|x
₁
(n-m)|+|x
₂
(n-m)) and (|x
₁
(n-m)|-|x
₂
(n-m)) two terms, avoids |x
₁
(n-m)|
^k-j
|x
₂
(n-m)|
^j
term to make the polynomial form simplified. A High efficiency Broadband GaN HEMT power amplifier is used to verify the model. The dual 20MHz band spacing 140MHz are test at the carrier frequency of 1.95GHz and 2.55GHz. After predistortion, ACPR is lower than - 49dBc. And the proposed model can get almost the same performance as 2D-DPD while saveing 27% coefficients.