电子学报 ›› 2016, Vol. 44 ›› Issue (5): 1254-1257.DOI: 10.3969/j.issn.0372-2112.2016.05.035

• 科研通信 • 上一篇    下一篇

Stokes参数数字化求解的误差分析

陆浩, 王振占, 刘璟怡, 李彬, 董帅   

  1. 中国科学院微波遥感技术重点实验室, 中国科学院国家空间科学中心, 北京 100190
  • 收稿日期:2013-12-04 修回日期:2015-08-28 出版日期:2016-05-25 发布日期:2016-05-25
  • 作者简介:陆浩 男,1988年生于安徽亳州,中科院博士.研究方向为大规模数字电路,微波辐射计系统研制和定标.E-mail:luhao0408@126.com;王振占 男,研究员1969年生于河北青龙县.研究方向为全极化微波辐射测量技术、定标和应用基础研究;微波辐射计海洋/大气微波辐射传输及参数的反演应用研究等.
  • 基金资助:

    中国科学院空间科学战略性先导科技专项(No.XDA04061200)

Error Analyze of Stokes Parameters Digital Solution

LU Hao, WANG Zhen-zhan, LIU Jing-yi, LI Bin, DONG Shuai   

  1. Key Laboratory of Microwave Remote Sensing, National Space Science Center, Chinese Academy of Sciences, Beijing 100190, China
  • Received:2013-12-04 Revised:2015-08-28 Online:2016-05-25 Published:2016-05-25

摘要:

Stokes参数是描述极化波的强度量纲,在电磁测量、合成孔径雷达、辐射计中均有广泛应用.文中提出了求解Stokes参数的数字化方法,具有带宽高、稳定性高等特点.针对将模拟信号采样量化后求解Stokes参数的方法,本文分别就自相关和互相关两种计算过程,详细分析并给出了数字量化对最终亮温的误差贡献.文中证明了高于3bit量化引入的亮温误差小于1*10-5K,进一步给出了量化后的系统灵敏度,分析了由数字量化产生的亮温灵敏度偏差.当量化位数为3bit时,数字相关系统灵敏度可以达到理想模拟相关系统的95%.本文为不同应用条件下,满足不同精度时,如何选择特定量化位数与量程提供了依据.

关键词: Stokes参数, 相关计算, 数字采样, 量化误差

Abstract:

Stokes parameter is the intensity dimension to describe polarized wave.Stokes parameter is widely used in electromagnetism measure, synthetic aperture and radiometer.The digital method given in the paper has the characters of high-bandwidth and high-stability.The measure error contributed by digital sampling for Stokes parameter solution is analyzed in detail in the paper.The brightness temperature quantization error under auto-correlation is proved to be less than 1*10-5K in application with 3 bits quantization.Further the paper gives the system sensitivity, analyzes the brightness temperature error generated by the digital quantization.When quantization is above 3 bits, the digital system sensitivity can achieve 95% of ideal analog system.The theory foundation of digitization solution is given to prove its feasibility for different demand in different device.

Key words: Stokes parameter, correlation, digital sample, quantization error

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