面向微型光谱仪在线检测的光学系统误差校正方法

微型光纤光谱仪由于具有小型化、集成化、检测速度快等特点,适合用于工业现场多组分物质的在线检测。针对微型光谱仪由于受到仪器杂散光、光度噪声和光源波动等因素的影响,导致测量光谱信号精度差的问题,提出了一种面向微型光谱仪在线检测的光学系统误差校正方法。该方法首先使用光谱仪在线测量光谱强度,并通过参考溶液和待测溶液获取光谱信号;其次,通过提出的自适应小波阈值去噪法,消除光谱信号的光度噪声,提升光谱信号的灵敏度;然后,提出了一种基于双波长光强比值不变性的光源稳定方法,动态消除光源误差;最后,对铜钴离子的光谱信号进行动态校正,并对校正曲线进行性能分析。结果表明,所提出的方法简单快速,适用于光谱信号的动态校正,以满足多金属杂质离子在线检测的需求。

Opto-mechanical-thermal integration analysis of Doppler asymmetric spatial heterodyne interferometer

In order to improve the detection accuracy of Doppler asymmetric spatial heterodyne(DASH)interferometer in harsh temperatures,an opto-mechanical-thermal integration analysis is carried out.Firstly,the correlation between the interference phase and temperature is established according to the working principle and the phase algorithm of the interferometer.Secondly,the optical mechanical thermal analysis model and thermal deformation data acquisition model are designed.The deformation data of the interference module and the imaging optical system at different temperatures are given by temperature load simulation analysis,and the phase error caused by thermal deformation is obtained by fitting.Finally,based on the wind speed error caused by thermal deformation of each component,a reasonable temperature control scheme is proposed.The results show that the interference module occupies the main cause,the temperature must be controlled within(20±0.05)℃,and the temperature control should be carried out for the temperature sensitive parts,and the wind speed error caused by the part is 3.8 m/s.The thermal drift between the magnification of the imaging optical system and the thermal drift of the relative position between the imaging optical system and the detector should occupy the secondary cause,which should be controlled within(20±2)℃,and the wind speed error caused by the part is 3.05 m/s.In summary,the wind measurement error caused by interference module,imaging optical system,and the relative position between the imaging optical system and the detector can be controlled within 6.85 m/s.The analysis and temperature control schemes presented in this paper can provide theoretical basis for DASH interferometer engineering applications.

一种针对高速小目标的偏航角测算方法

射弹偏航角是影响电磁轨道发射装置发射精度的关键参数,为实时、高精度测量射弹偏航角,提升电磁轨道发射装置发射精度,基于双目视觉原理提出一种无需目标速度的射弹偏航角测算方法。利用高速射弹轨迹图像,通过构建像机线性成像模型解算高速射弹图像坐标,实现目标偏航角的测量。分析了光学系统参数对测量精度的影响,理论误差约为14.5μrad。偏航角测量实验结果表明该方法能够实时、准确测算射弹偏航角,测算量偏差平均值为0.58mrad。

PCCC for the performance improvement of the wireless optical communication system

In wireless optical communication, effects of scintillation make average Bit Error Rate （BER） deteriorate. To improve system performance,PCCC （Parallel Concatenated Convolutional Code） encoding scheme is employed,and upper bound on the bit error rate is given by considering the effects of scintillation,APD noise and thermal noise. Simulation results show that the POOC encoding scheme can relieve turbulenceinduced intensity fluctuations and the system performance is improved remarkably.

Improved FEC Code Based on Concatenated Code for Optical Transmission Systems

The improved three novel schemes of the super forward error correction （super-FEC） concatenated codes are proposed after the development trend of long-haul optical transmission systems and the defects of the existing FEC codes have been analyzed. The performance simulation of the Reed-Solomon（RS）＋ Bose-Chaudhuri-Hocguenghem（BCH） inner-outer serial concatenated code is implemented and the conceptions of encoding/decoding the parallel-concatenated code are presented. Furthermore, the simulation results for the RS（255,239） ＋RS（255,239） code and the RS（255,239） ＋RS（255,223） code show that the two consecutive concatenated codes are a superior coding scheme with such advantages as the better error correction, moderate redundancy and easy realization compared to the classic RS（255,239） code and other codes, and their signal to noise ratio gains are respectively 2-3 dB more than that of the RS（255,239）code at the bit error rate of 1 × 10^-13. Finally, the frame structure of the novel consecutive concatenated code is arranged to lay a firm foundation in designing its hardware.

The research on signal-obtaining pattern for a new type of gyroscope

In this paper, a photoelectric signal obtained scheme via equator triangle pattern engraved on rotor is discussed and the mathematic model is deduced in the case which is deflexion between rotor axis and the coordinate frame of case. The deflexion error and coupling error under the situation are analyzed. Finally, three methods of engraving based on the spherical triangle pattern are presented. The error models of various methods are built up and the simulation curves are provided respectively. We have done the primary experiments on the surface of rotor using this method. It can be seen from the enlarged figures that the rim of the pattern is smooth and the demand of sensor resolution is satisfied by and large. The results of study supply reference for signal obtaining.

Channel Arrangement for optical communication subsystems with 12 parallel channels

This paper devoted to report the design and the achievement of an optical communication subsystem with 12 parallel channels in one chip.The system is capable of transmitting 10 Gbps bidirectional date over hundreds of meters.It can provide error detection and correction by using 8B/10B encoding and Cyclical Redundancy Checking (CRC) encoding when only single-channel fails.The design scheme has already passed the simulation in FPGA.This technique is useful to enhance the capability and the reliability of the very short reach (VSR) transmission systems.

浅谈投影仪测量误差产生的原因及其排除方法

文章概述了投影仪常见测量误差产生的原因,介绍了投影仪出现放大倍率误差、灯丝长度误差、二次调焦误差、像倾斜、像模糊的排除方法。