应用频率误差修正的高灵敏度GPS信号捕获技术
DOI: 10.3969/j.issn.1006-7043.2009.08.007
Keywords: GPS 灵敏度 差分相干捕获 频率误差修正
Abstract:
为提高弱信号环境下GPS捕获的灵敏度和频率精度,分析了差分相干捕获的输出特性,并对捕获频率误差的分布性进行理论推导.在此基础上提出在捕获过程中将频率误差修正值通过反馈环路实时引入本地振荡器,使修正后的sinc项趋近于1.理论分析与性能评估结果表明,差分相干输出近似服从高斯分布,提出的方案在处理低信噪比的GPS信号时,灵敏度优于非相干法2 dB、标准差分法0.5 dB;在给定的积分时间下,捕获得到的多普勒频率均值与实际值的误差小于5 Hz,标准差小于20 Hz,而且具有捕获频率精度随积分时间增加而提高的优点,能够满足后续弱信号跟踪要求.
| [1] | 1. ZHENG B.LACHAPELLE G GPS software receiver enhancements for indoor use 2005
|
| [2] | 2. JAMES B Y T Fundamentals of global positioning system receivers:a software approach 2004
|
| [3] | 3. ZARRABIZADEH M H.SOUSA E S A differentially coherent PN code acquisition receiver for CDMA systems 1997(11)
|
| [4] | 4. CHOI H.CHO D J.YUN S J A novel weak signal acquisition scheme for assisted GPS 2002
|
| [5] | 5. PARK S H.CHOI H.LEE S A novel GPS initial synchronization scheme using decomposed differential matched filter 2002
|
| [6] | 6. O’ DRISCOLL C Performance analysis of the parallel acquisition of weak GPS signals 2007
|
| [7] | 7. SCHMID A.GUNTHER C.NEUBAUER A frequency offset estimation for Galileo/GPS receivers based on differential correlation 2005
|
| [8] | 8. 董渊文.官洪运.胡辉.储新惠 基于FFT的GPS接收机伪码捕获算法研究 2007(2)
|
| [9] | 9. RODRIGUEZ J A A.PANY T.EISSFEIJ ER B A theoretical analysis of acquisition algorithms for indoor positioning 2004
|
| [10] | 10. WEISSTEIN E W Normal product distribution 2008
|
| [11] | 11. ABRAMOWlTZ M.STEGUN A Handbook of mathematical functions 1970
|
| [12] | 12. WEI Yu.BO Zheng.WATSON R Differential combining for acquiring weak GPS signals 2007(5)
|
| [13] | 13. PROAKIS J G Digital communications 2001
|
| [14] | 14. SIMON M K Probability distributions involving Gaussian random variables:a handbook for engineers and scientists 2002
|
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