The Digital RF Modulation Strategy Based on Area Equivalent Theory
CHEN Jian-bin1,2, ZHANG Jiang2, ZHOU Qiang2
1. College of Communications Engineering, Army Engineering University of PLA, Nanjing, Jiangsu 210007, China;
2. . 63 rd Research Institute, National University of Defense Technology, Nanjing, Jiangsu 210007, China
Abstract：In order to drive the switched mode power amplifier (SMPA) for full-digital transmitter,the input Radio Frequency (RF) signal of full-digital transmitter first needs to be transformed into pulse sequences by using the digital RF modulator.Considering the disadvantages in modulation performance and system realization of existing digital RF modulation strategies,especially the Pulse Width Modulation (PWM) and Delta-Sigma Modulation (DSM),a digital RF modulation strategy was proposed and analyzed in this paper by using the area equivalent theory.The theoretical analysis and simulation results show that,compared to the PWM and DSM,the proposed modulation strategy not only reduces the hardware implementation difficulty,but also achieves better performance of the SNR and coding efficiency.
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2019, Vol. 47 
