摘要
由于炉膛背景噪声的影响和实际中用于互相关运算的采样点数不可能无限大,声学测温系统中采用的互相关函数测量的声波飞渡时间的方法是存在误差的。文章从理论上给出了这一误差的方差表达式,并分析了影响这一误差的因素,通过选取合适的互相关运算点数。采样频率和具有尖锐自相关特性的声波信号,能有效降低这一测量误差。
There is an error in acoustic pyrometer using cross-correlation to measure the acoustic waves flight time because of the finite sampling points and the strong noise from burning. In this paper, the variance of the error and the factor associated with it are given. In order to reduce this error, the .sampling frequency, the number of the .sampling points and the acoustic waves with better correlation characteristic should be adequately selected.
出处
《电力科学与工程》
2006年第1期45-47,共3页
Electric Power Science and Engineering
基金
教育部高等学校博士学科点专项科研基金(20050079004)
关键词
声学测温
互相关
误差方差
acoustic measurement
cross-correlation
variance of the error