Zhaobo Zhang, Chenchang Zhan, Man-Kay Law, Yang Jiang, Pui-In Mak, Rui P. Martins,
          
          
          
            A High-Efficiency Dual-Antenna RF Energy Harvesting System using Full-Energy Extraction with Improved Input Power Response          
          
          
                    
            IEEE Open Journal of Circuits and Systems
          
          
                    
            vol. 2, pp. 436–444          
                    
                                   
                                Jul-2021