基于小波变换的蓝宝石荧光光纤温度计

采用激光加热小基座法生长出掺Cr3+的蓝宝石光纤荧光温度传感头，它具有结构紧凑，耐高温等特点，测温范围从室温到450℃。使用基于小波变换的数据处理方法，有效去除信号中的噪声，提高了信噪比。在对荧光测温机理和有关光纤技术进行分析的基础上，采用与调制荧光信号相关的双参考源相位锁定测量方案，可在无激励光干扰的情况下对荧光寿命进行实时测量。根据噪音和信号在小波变换下表现出的不同性质，提出以小波变换为基础的温度信号特征提取及消噪方法。与其它处理方法相比，小波变换方法可以克服傅里叶变换对突变信号不起作用的缺点，同时又比Gabor变换具有可变窗口的优点。该方法可以缩短测量时间，提高测量分辨率。

Sapphire fiber thermal probe based on wavelet transform

A sapphire fiber fluorescence thermal probe with Cr3+ ion-doped end was grown from the laser heated pedestal growth method. The fluorescence thermal probe offers the advantages of compact in structure,high performance and ability to detect temperature ranging from the room temperature to 450 C. The data processing based on the wavelet transform can effectively decrease the noise out of the signal so that the signal-to-noise ratio can be improved. Based on the theoretical analysis of the fluorescence temperature measurement methodology and fiber technology,a phase-lock loop technology is adopted to make the real-time measurement without the interference of the exciting light. Taking advantage of the different features indicated by noise and signal when wavelet transformation is applied,the temperature signal extraction and noise elimination method based on the wavelet transformation theory is given. In comparison with other processing methods,the wavelet transform method overcomes the shortcoming in the fast Fourier transform and can be applied to mutation signals,and it has a variable window that the Gabor transform does not has. Therefore,the method can shorten the process of signal processing and improve the measurement resolution.