DPD based HPA linearizer using in-band operation point estimation pilot for mobile device applications

摘要

HPA (High Power Amplifier) linearizer is widely used to reduce ACLP (Adjacent Channel Leakage Power) for higher spectrum efficiency and to improve power efficiency of HPA, however it has not been used in mobile devices since it needs an additional receiver to monitor ACLP at HPA output. To apply DPD (Digital Pre-Distortion) based HPA linearized in mobile devices, this paper proposes a DPD based HPA linearizer using in-band operation point estimation pilot for mobile device applications. The proposed HPA linearizer uses look-up table of HPA input-output characteristics in a mobile device. In addition, the proposed scheme uses in-band pilot signal to estimate the operation point of HPA linearizer, thus it does not need an additional receiver to control HPA linearizer and can simplify mobile device implementation. This paper describes the design of the pilot signal for HPA operation point estimation and its estimation performance.