Synthetic aperture radar(SAR)radio frequency identification(RFID)localization is widely used for automated guided vehicles(AGVs)in the industrial internet of things(IIoT).However,the AGV’s speeds are limited by the p...Synthetic aperture radar(SAR)radio frequency identification(RFID)localization is widely used for automated guided vehicles(AGVs)in the industrial internet of things(IIoT).However,the AGV’s speeds are limited by the phase difference(PD)of two neighboring readers.In this paper,an inertial navigation system(INS)based SAR RFID localization method(ISRL)where AGV moves nonlinearly.To relax the speed limitation,a new phase-unwrapping method based on the similarity of PDs(PU-SPD)is proposed to deal with the PD ambiguity when the AGV speed exceeds 60km/h.In localization,the gauss-newton algorithm(GN)is employed and an initial value estimation scheme based on variable substitution(IVE-VS)is proposed to improve its positioning accuracy and the convergence rate.Thus,ISRL is a combination of IVE-VS and GN.Moreover,the Cramer-Rao lower bound(CRLB)and the speed limitation is derived.Simulation results show that the ISRL can converge after two iterations,and the positioning accuracy can achieve 7.50cm at a phase noise levelσ=0.18,which is 35%better than the Hyperbolic unbiased estimation localization(HyUnb).展开更多
基金supported by the National Natural Science Foundation of China under Grant U21A20449The Zhongguancun Project under Grant 23120035.
文摘Synthetic aperture radar(SAR)radio frequency identification(RFID)localization is widely used for automated guided vehicles(AGVs)in the industrial internet of things(IIoT).However,the AGV’s speeds are limited by the phase difference(PD)of two neighboring readers.In this paper,an inertial navigation system(INS)based SAR RFID localization method(ISRL)where AGV moves nonlinearly.To relax the speed limitation,a new phase-unwrapping method based on the similarity of PDs(PU-SPD)is proposed to deal with the PD ambiguity when the AGV speed exceeds 60km/h.In localization,the gauss-newton algorithm(GN)is employed and an initial value estimation scheme based on variable substitution(IVE-VS)is proposed to improve its positioning accuracy and the convergence rate.Thus,ISRL is a combination of IVE-VS and GN.Moreover,the Cramer-Rao lower bound(CRLB)and the speed limitation is derived.Simulation results show that the ISRL can converge after two iterations,and the positioning accuracy can achieve 7.50cm at a phase noise levelσ=0.18,which is 35%better than the Hyperbolic unbiased estimation localization(HyUnb).
