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Detection performance improvement of photon counting chirped amplitude modulation lidar with response probability correction
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Geiger mode avalanche photodiode detector(Gm-APD) possesses the ultra-high sensitivity. Photon counting chirped amplitude modulation(PCCAM) light detection and ranging(lidar) uses the counting results of the returned signal detected by Gm-APD to mix with the reference signal, which makes PCCAM lidar capable of realizing the ultra-high sensitivity, and this is very important for detecting the remote and weak signal. However, Gm-APD is a nonlinear device, different from traditional linear detectors. Due to the nonlinear response of Gm-APD, the counting results of the returned signal detected by Gm-APD are different from those of both the original modulation signal and the reference signal. This will affect the mixing effect and thus degrade the detection performance of PCCAM lidar. In this paper, we propose a response probability correction method. First, the response probability correction model is established on the basis of Gm-APD Poisson probability response model. Then, the response probability correction model is used to adjust the original modulation signal that is used to drive laser, in order to make the counting results of the returned signal detected by Gm-APD better mix with the local reference signal in the same form. Through this method, the detection performance of PCCAM lidar is enhanced efficiently. 相似文献
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The intensity detection of single-photon detectors based on photon counting probability density statistics
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Single-photon detectors possess the ultra-high sensitivity, but they cannot directly respond to signal intensity. Conventional methods adopt sampling gates with fixed width and count the triggered number of sampling gates, which is capable of obtaining photon counting probability to estimate the echo signal intensity. In this paper, we not only count the number of triggered sampling gates, but also record the triggered time position of photon counting pulses. The photon counting probability density distribution is obtained through the statistics of a series of the triggered time positions. Then Minimum Variance Unbiased Estimation(MVUE) method is used to estimate the echo signal intensity. Compared with conventional methods, this method can improve the estimation accuracy of echo signal intensity due to the acquisition of more detected information. Finally, a proof-of-principle laboratory system is established. The estimation accuracy of echo signal intensity is discussed and a high accuracy intensity image is acquired under low-light level environments. 相似文献
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Super-resolution and super-sensitivity of entangled squeezed vacuum state using optimal detection strategy
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Interference metrology is a method for achieving high precision detection by phase estimation. The phase sensitivity of a traditional interferometer is subject to the standard quantum limit, while its resolution is constrained by the Rayleigh diffraction limit. The resolution and sensitivity of phase measurement can be enhanced by using quantum metrology. We propose a quantum interference metrology scheme using the entangled squeezed vacuum state, which is obtained using the magic beam splitter, expressed as |ψ〉=(|ξ〉|0〉+|0〉|ξ〉)/(2+2/coshr)~(1/2), such as the N00 N state. We derive the phase sensitivity and the resolution of the system with Z detection, project detection, and parity detection. By simulation and analysis, we determine that parity detection is an optimal detection method, which can break through the Rayleigh diffraction limit and the standard quantum limit. 相似文献
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Spatially modulated scene illumination for intensity-compensated two-dimensional array photon-counting LiDAR imaging
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Jiaheng Xie 《中国物理 B》2022,31(9):90701-090701
Photon-counting LiDAR using a two-dimensional (2D) array detector has the advantages of high lateral resolution and fast acquisition speed. The non-uniform intensity profile of the illumination beam and non-uniform quantum efficiency of the detectors in the 2D array deteriorate the imaging quality. Herein, we propose a photon-counting LiDAR system that uses a spatial light modulator to control the spatial intensity to compensate for both the non-uniform intensity profile of the illumination beam, and the variation in the quantum efficiency of the detectors in the 2D array. By using a 635 nm peak wavelength and 4 mW average power semiconductor laser, lab-based experiments at a 4.27 m stand-off distance are performed to verify the effectiveness of the proposed method. Compared with the unmodulated method, the standard deviation of the intensity image of the proposed method is reduced from 0.109 to 0.089 for a whiteboard target, with an average signal photon number of 0.006 per pixel. 相似文献
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