A 2.5GHZ-2.7GHz Unsymmetrical Doherty Power Amplifier with Digital Predistortion for LTE-Advanced Applications

Abstract:

An unsymmetrical GaN based Doherty power amplifier (DPA) operating from 2.5GHz to 2.7GHz is presented in this paper. To achieve a good tradeoff among the output power, efficiency and bandwidth, the ladder-type multisection output matching networks are optimized for the carrier amplifier and the peaking amplifier, respectively. Measured with continuous wave (CW) signal, the broadband DPA provides more than 49dBm saturation power in the operating band. The drain efficiency is greater than 44% over 7dB back-off power. For a LTE-Advanced signal with 100MHz bandwidth, the drain efficiency is higher than 42% at an average output power of 41dBm, along with an adjacent channel leakage ratio (ACLR) of better than-49.9dBc after digital predistortion (DPD).

• Periodical: Advanced Materials Research (Volumes 760-762)
• Pages: 546-550
• DOI: https://doi.org/10.4028/www.scientific.net/AMR.760-762.546
• Online since: September 2013
• Authors: Wen Sheng Pan, Chuan Hui Ma, Shi Hai Shao, You Xi Tang
• Keywords: Digital Predistortion, Doherty Power Amplifier, Output Matching Networks, Unsymmetrical

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