【摘要】 本文介绍一个采用FFT分析仪与计算机的低频噪声谱自动测量系统,它具有测量频率范围宽(1Hz～100kHz)、测量过程自动化及实时数据处理等优点。重点讨论了低频噪声谱的测量误差,包括测量结果期望值与真值的相对偏差以及随机起伏引起的方差。理论和实验表明,在低频段采用数据记录长度4s、平均1024次后,可达到优于4％的测量精确度。更多还原

【Abstract】 In this paper an automatic low-frequency noise spectral densitymeasurement system using a FFT analyzer and a computer is described. The advantages of this system are. wide-range of measurement frequency (1 Hz~100 kHz), automatic measurement control and real time data processing. The measurement errors are also discussed. They are. (1) the partial difference between the expectation value of measurement result and the true value of the noise spectrum; (2) the random variance of the measurement result. The theoretical analysis and experiment result demonstrated that the measurement accuracy in low-frequency range is better than 4% on condition that the data record length is 4s and take an average over 1024 times.更多还原