光电探测器暗电流宽温拟合算法研究  

Study of Wide-temperature Fitting Algorithm for PD Dark Current

作　　者：袁国振 任海兰[1] YUAN Guozhen;REN Hailan(Wuhan Research Institute of Posts and Telecommunication,Wuhan 430074,China;Wuhan Molex Communication Technology Co.,Ltd.,Wuhan 430070,China)

机构地区：[1]武汉邮电科学研究院,武汉430074 [2]武汉莫仕通讯技术有限公司,武汉430070

出　　处：《光通信研究》2025年第1期77-82,共6页Study on Optical Communications

摘　　要：【目的】为了消除光电探测器(PD)内正负(PN)结固有暗电流物理特性的影响,在提升探测器功率探测范围和扩宽探测器工作环境温度范围的同时提高PD探测精度,文章设计了一套在标定PD时应用的暗电流补偿算法。【方法】首先,通过分析光电二极管物理特性及PD内的硬件电路设计,建立光生电流与光功率间的数学模型,基于数学模型修正光功率与光生电压模数转换(ADC)值的曲线关系,实现在具体温度点下去除暗电流功率影响并补偿功率;其次,研究暗电流的温度特性,计算出少数温度条件下所需补偿暗电流的功率大小,利用少数温度点拟合扩展至宽温范围实现暗电流温度补偿;最后,搭建温控测试平台,利用光开关(OS)控制光电二极管入光功率大小,通过光功率探测仪记录PD实时入光功率大小,测试在不同温度条件以及入光功率下的PD精度值。【结果】实验表明,利用算法标定PD后,工作温度范围可从-5~55℃扩宽至-40~80℃,最低探测功率从-40下降至-68 dBm。在上述工作温度和探测范围下,软件算法计算上报的光功率与实际探测光功率的精度误差在±1 dB以内。【结论】采用文章所提算法对PD校准后能消除暗电流及噪声的影响,在宽温范围下能提高探测功率范围及探测精度。【Objective】In order to eliminate the influence of the physical characteristics of the intrinsic dark current of the Positive-Negative(PN)junction in the Photoelectric Detector(PD),the detection accuracy of the PD can be improved at the same time of enhancing the detection range of the detector power and widening the detector working environment temperature.In this paper,a set of dark current compensation algorithms is designed to calibrate the PDs.【Methods】Firstly,we analyze the physical characteristics of the photodiode and the hardware circuit design of the PD to establish a mathematical model between the photogenerated current and the optical power.Then we correct the curve relationship between the optical power and the Analog Digital Convert(ADC)value of the photogenerated voltage through the mathematical model,so as to achieve the power compensation by removing the influence of the dark current power at the specific temperature point.Next,by studying the temperature characteristics of dark current,we calculate the power required to compensate for dark current under a limited number of temperature conditions.By fitting these few temperature points,we extend the compensation to a broader temperature range,thereby achieving dark current temperature compensation.Lastly,a temperature-controlled testing platform is established,utilizing an Optical Switch(OS)to regulate the incident optical power on the photodiode.The real-time incident optical power on the PD is recorded through an optical power meter.This setup allows for testing the accuracy of the PD under various temperature conditions and incident optical power levels.【Results】The experiments show that the working temperature can be widened from-5~55℃to-40~80℃and the minimum detection power can be reduced from-40 to-68 dBm by using the algorithm to calibrate the photo-detector.Under the aforementioned operating temperature and detection range,the software algorithm calculates the accuracy error between the reported optical power and the actual

关 键 词：暗电流 光电探测器 宽温范围 低功探测 补偿算法 

分 类 号：TN256[电子电信—物理电子学]