A design of DDS single-frequency signal generator based on phrase jitter technology to reduce scattering noise
Liu, Zhihui1,2,3; Fan, Muwen1,2; Zhou, Luchun1,2
2015
会议名称Proceedings of SPIE - The International Society for Optical Engineering
会议日期2015
卷号9675
页码96750W
中文摘要In order to test the working status of adaptive optics systems, it is necessary to design a disturbance signal module. Disturbance signal module based on DDS (Direct Digital frequency Synthesis) is used to generate single-frequency disturbance signal to test the working conditions of deformable mirror and adaptive optics systems. But DDS is a periodic sampling sequence and will inevitably lead to the introduction of periodic noise which makes the disturbance signal scattering. This paper uses two methods to reduce the scattering of the single-frequency signal generated by DDS technology. The first method is the compression ROM table. In the case of the same ROM capacity, it is equivalent to extend the compressed ROM table with 256 points to ROM table with 1024 points. In this process, Oversampling is introduced to improve spectral purity to reduce the scattering of the single-frequency signal. The second method is the random phase jitter technology. It introduces m sequence as DDS sampling output random phase jitter unit. The purpose is to generate some random number added at the end of the phase accumulator. As a result, the output does not always push back than ideal, but randomly in advance, thus breaking its periodicity. This method changes the original uniform look-up sampling into a random non-uniform look-up sampling, making DDS output spectrum white. It can also improve spectral purity of the DDS output, thereby reducing the scatting of the single-frequency signal generated by DDS technology. © 2015 SPIE.
英文摘要In order to test the working status of adaptive optics systems, it is necessary to design a disturbance signal module. Disturbance signal module based on DDS (Direct Digital frequency Synthesis) is used to generate single-frequency disturbance signal to test the working conditions of deformable mirror and adaptive optics systems. But DDS is a periodic sampling sequence and will inevitably lead to the introduction of periodic noise which makes the disturbance signal scattering. This paper uses two methods to reduce the scattering of the single-frequency signal generated by DDS technology. The first method is the compression ROM table. In the case of the same ROM capacity, it is equivalent to extend the compressed ROM table with 256 points to ROM table with 1024 points. In this process, Oversampling is introduced to improve spectral purity to reduce the scattering of the single-frequency signal. The second method is the random phase jitter technology. It introduces m sequence as DDS sampling output random phase jitter unit. The purpose is to generate some random number added at the end of the phase accumulator. As a result, the output does not always push back than ideal, but randomly in advance, thus breaking its periodicity. This method changes the original uniform look-up sampling into a random non-uniform look-up sampling, making DDS output spectrum white. It can also improve spectral purity of the DDS output, thereby reducing the scatting of the single-frequency signal generated by DDS technology. © 2015 SPIE.
收录类别SCI ; EI
学科主题Adaptive optics - Image analysis - Image processing - Jitter - Optical data processing - Optical testing - Random number generation
语种英语
ISSN号0277-786X
内容类型会议论文
源URL[http://ir.ioe.ac.cn/handle/181551/7836]  
专题光电技术研究所_自适应光学技术研究室(八室)
作者单位1.Institute of Optics and Electronics, Chinese Academy of Sciences, Chengdu, Sichuan, China
2.Key Laboratory on Adaptive Optics, Chinese Academy of Sciences, Chengdu, Sichuan, China
3.College of Materials Science and Opto-electronic Technology, University of Chinese Academy of Sciences, Beijing, China
推荐引用方式
GB/T 7714
Liu, Zhihui,Fan, Muwen,Zhou, Luchun. A design of DDS single-frequency signal generator based on phrase jitter technology to reduce scattering noise[C]. 见:Proceedings of SPIE - The International Society for Optical Engineering. 2015.
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