Demonstration on the design of filter indexes of inter-satellite high accuracy ranging system for gravity satellite

作者：Kang Kai-Xuan^*; Li Hui; Wu Yun-Long; Zou Zheng-Bo; Xing Le-Lin

来源：Acta Geophysica Sinica, 2012, 55(10): 3240-3247.

DOI：10.6038/j.issn.0001-5733.2012.10.006

• Gravity satellite
• Inter-satellite high accuracy ranging system
• The design of filter indexes
• GRACE
• KBR

In order to value the sensitivity of inter-satellite ranging measurements related to gravity field for the satellite-to-satellite tracking model, sensitivity matrix analysis, which is a method of estimating the influence of input parameters on the system model, is applied in this paper. For the inter-satellite high accuracy ranging measurements of gravity satellite, we describe the theory of spectrum analysis of sensitivity matrix for inter-satellite ranging measurements, calculate main sensitivity matrix based on the Kepler satellite orbit for GRACE, analyze the spectrum characteristic of sensitivity matrix for different degree coefficients of gravity field, and explain our results in view of the character of Legendre functions and spherical harmonic functions. In addition, in order to prove the conclusion on spectrum characteristic we simulate several main sensitivity factors for inter-satellite ranging measurements based on gravity field of independent n degree m order spherical harmonic functions and find good agreement between our simulated models and theory models. Considering the effects of conservative force, non-conservative force and inter-satellite measurement noise, we discuss the effective frequency band of inter-satellite ranging measurements in which the gravity field signal is contained, and get the conclusion that for n degree gravity field the upper limit of effective frequency band is due to the spectrum of sensitivity matrix of n degree zonal spherical harmonics. Based on the results of gravity signal band, we demonstrate the design of low-pass filter indexes, such as cut frequency of pass-band, gain ripple specifications of pass-band and frequency sample rate, and show the design for current GRACE mission, future GRACE Follow-on mission and our national gravity satellite mission in details. Our results are based on the spectral relationship between sensitivity matrix for inter-satellite ranging measurements and gravity potential, improving the previous methods which are mainly based on the high-frequency noise of inter-satellite ranging measure meters. The results of this paper are able to be applied in the design of the major technique indexes for our future gravity satellite mission.

• 出版日期2012-10
• 单位武汉大学; 中国地震局地震研究所