Title :
Combining Crest Factor Reduction and digital predistortion with automatic determination of the necessary Crest Factor Reduction gain
Author :
Mbaye, Amadou ; Baudoin, Genevieve ; Gouba, Abel ; Louet, Yves ; Villegas, Martine
Author_Institution :
ESYCOM, Univ. Paris-Est, Noisy-le-grand, France
Abstract :
Digital predistortion (DPD) and Crest Factor Reduction (CFR) are applied separately in radio frequency power amplifiers (PAs) in general. This paper proposes a method to jointly optimize DPD and CFR. For a given model of predistorter our solution gives automatically the Peak to average power ratio (PAPR) reduction gain to be applied by the CFR module. Within the DPD module PAPRs of original input signal and PA output and PAPR at predistorter output without CFR are used to estimate an optimal CFR gain through mathematical calculations. The combined CFR/DPD module ensures that the PAPR at the output of predistorter will not exceed a given limit. Hence, the envelope clipping module which is typically present to protect the PA, may be removed. In addition the proposed method offers a higher operating range of the DPD while fulfilling out-of band requirements and preserving low in-band distortion. Power efficiency of amplification module is improved as well. This solution has been tested by simulation and on a class AB LDMOS power amplifier in Agilent Advanced Design System (ADS).
Keywords :
amplification; limiters; optimisation; radiofrequency power amplifiers; amplification module; automatic determination; crest factor reduction; digital predistortion; peak to average power ratio reduction gain; power efficiency; radio frequency power amplifiers; Gain; Mathematical model; Peak to average power ratio; Polynomials; Power amplifiers; Radio frequency;
Conference_Titel :
Microwave Conference (EuMC), 2014 44th European
Conference_Location :
Rome
DOI :
10.1109/EuMC.2014.6986565