We propose a method for reconstructing non-diffuse surfaces based on theπ-phase-shifted two-plus-one phase-shifting method.First,we introduce a 2fH+a+2fM+2f_(L)method for unwrapped phase extraction.Subsequently,we in...We propose a method for reconstructing non-diffuse surfaces based on theπ-phase-shifted two-plus-one phase-shifting method.First,we introduce a 2fH+a+2fM+2f_(L)method for unwrapped phase extraction.Subsequently,we introduce a new set ofπ-phase-shifted 2fH+a/2+2fM+2f_(L)fringe patterns with halved background intensity.The saturated pixels will be replaced with the unsaturated pixels in theπ-phase-shifted fringe patterns.Finally,we analyze eight fringe replacement cases and give the corresponding phase calculation,and further give the general formulas.Experiments confirm that the sum of the phase error of the proposed method is 81.4%lower than that of the traditional method,and 61.5%lower than that of the adaptive fringe projection method.展开更多
为了在π/4-DQPSK解调中能快速实现位同步捕获和跟踪,提出将中频差分检测和同步头捕获跟踪相结合的并行处理方法,根据π/4-DQPSK本身的特点,按照π/4-DQPSK解调中的快速同步捕获和位同步跟踪改进算法,结合信号能量检测、频移初捕并行处...为了在π/4-DQPSK解调中能快速实现位同步捕获和跟踪,提出将中频差分检测和同步头捕获跟踪相结合的并行处理方法,根据π/4-DQPSK本身的特点,按照π/4-DQPSK解调中的快速同步捕获和位同步跟踪改进算法,结合信号能量检测、频移初捕并行处理的位定时算法,采用FPGA(fied program grid array)技术实现π/4-DQPSK解调中的快速同步捕获和位同步跟踪。实验结果表明最快可以在8个符号位时稳定恢复时钟同步信号,具有捕获周期短,位定时准确,抗干扰能力强,不受频差影响,适合于高传输码率的跳频通信接收系统应用。展开更多
基金supported by the Natural Science Foundation of Shandong Province(Nos.ZR2021MF024 and ZR2020QF101)the National Natural Science Foundation of China(Nos.62273274 and 62001263).
文摘We propose a method for reconstructing non-diffuse surfaces based on theπ-phase-shifted two-plus-one phase-shifting method.First,we introduce a 2fH+a+2fM+2f_(L)method for unwrapped phase extraction.Subsequently,we introduce a new set ofπ-phase-shifted 2fH+a/2+2fM+2f_(L)fringe patterns with halved background intensity.The saturated pixels will be replaced with the unsaturated pixels in theπ-phase-shifted fringe patterns.Finally,we analyze eight fringe replacement cases and give the corresponding phase calculation,and further give the general formulas.Experiments confirm that the sum of the phase error of the proposed method is 81.4%lower than that of the traditional method,and 61.5%lower than that of the adaptive fringe projection method.
文摘为了在π/4-DQPSK解调中能快速实现位同步捕获和跟踪,提出将中频差分检测和同步头捕获跟踪相结合的并行处理方法,根据π/4-DQPSK本身的特点,按照π/4-DQPSK解调中的快速同步捕获和位同步跟踪改进算法,结合信号能量检测、频移初捕并行处理的位定时算法,采用FPGA(fied program grid array)技术实现π/4-DQPSK解调中的快速同步捕获和位同步跟踪。实验结果表明最快可以在8个符号位时稳定恢复时钟同步信号,具有捕获周期短,位定时准确,抗干扰能力强,不受频差影响,适合于高传输码率的跳频通信接收系统应用。
