摘要
针对航天测控系统中数字基带设备误码率(BER)闭环自测无法溯源的问题,提出了采用误差矢量幅度(EVM)和相位噪声作为间接评价方法。分析了在加性高斯白噪声下的EVM和BER之间的关系,并给出了使用EVM预测BER的经验公式;分析了相位噪声对BER的影响方式,为相位噪声突变情况下的BER预测提供了依据;以单台基带设备为测试对象,在建立EVM与BER预测关系式后,将后续3个月内预测和测试的结果进行对比,对比结果最大相对偏差不大于12.5%。实验表明,在加性白噪声的情况下,使用EVM和相位噪声替代BER作为评价指标是可行的,且EVM更直观、更能直接体现过程影响量、有利于基带设备的溯源。
A method using EVM and phase noise to evaluate the digital baseband equipment is proposed instead of BER for it is self-tested in close-loop and can＇ t be traceable. The relationship between EVM and BER in additive white Gaussian noise is analyzed and the empirical formula using EVM to predict BER is given. The effect of phase noise on BER is analyzed providing a way to predict BER when the phase noise come to a sharp change. A digital baseband equipment for testing object, the difference between the predicted results and the measured results is no bigger than 12. 5% in 3 months after the predicting formula is established. The results show that the use of EVM and phase to evaluate the performance of the digital baseband equipment instead of BER is available in additive white Gaussian noise environment. What＇ s more, EVM reflects the effects in process directly and can be traced to the national standard.
出处
《计量学报》
CSCD
北大核心
2017年第2期230-233,共4页
Acta Metrologica Sinica
