Firstly, a new analytical error model of the cumulative geoid height using the three-dimensional diagonal tensors of satellite gravity gradiometry (SGG) is introduced based on the variance-covariance matrix principl...Firstly, a new analytical error model of the cumulative geoid height using the three-dimensional diagonal tensors of satellite gravity gradiometry (SGG) is introduced based on the variance-covariance matrix principle. Secondly, a study for the requirements demonstration on the next-generation GOCE Follow-On satellite gravity gradiometry system is developed using different satellite orbital altitudes and measurement accuracies of satellite gravity gradiometer by the new analytical error model of SGG. The research results show that it is preferable to design satellite orbital altitudes of 300 km–400km and choose the measurement accuracies of 10-13/s2 –10-15/s2 from satellite gravity gradiometer. Finally, the complementarity of the four-stage satellite gravity missions, including past CHAMP, current GRACE, and GOCE, and next-generation GOCE Follow-On, is contrastively demonstrated for precisely recovering the Earth’s full-frequency gravitational field with high spatial resolution.展开更多
This paper presents the field test of our first demonstration cluster with five base stations (BTS) on code division multiple access (CDMA) wireless communication in China, while each BTS was installed with a high tem...This paper presents the field test of our first demonstration cluster with five base stations (BTS) on code division multiple access (CDMA) wireless communication in China, while each BTS was installed with a high temperature superconductor (HTS) receiver. The HTS receivers have the same centre frequency of 830 MHz, a bandwidth of 13 MHz, and a noise figure (NF) of 0.9 dB. After the conventional receivers in the BTSs were replaced by the HTS receivers, a consequent drive test was carried out. A 2.35 dB decrease of the mean mobile transmit power was observed in the demonstration cluster.展开更多
基金Project supported by the Main Direction Program of Knowledge Innovation of Chinese Academy of Sciences for Distinguished Young Scholar (Grant No. KZCX2-EW-QN114)the National Natural Science Foundation of China for Young Scholar (Grant Nos. 41004006, 41131067, 11173049, and 41202094)+5 种基金the Merit-based Scientific Research Foundation of the State Ministry of Human Resources and Social Security of China for Returned Overseas Chinese Scholars(Grant No. 2011)the Open Research Fund Program of the Key Laboratory of Computational Geodynamics of Chinese Academy of Sciences (Grant No. 2011-04)the Open Research Fund Program of the Key Laboratory of Geospace Environment and Geodesy, Ministry of Education, China (Grant No. 11-01-02)the Open Research Fund Program of the Key Laboratory of Geo-Informatics of National Administration of Surveying, Mapping and Geoinformation of China(Grant No. 201322)the Open Fund of State Key Laboratory of Oil and Gas Reservoir Geology and Exploitation (Grant No. PLN1113)the Foundation of State Key Laboratory of Petroleum Resources and Prospecting, China University of Petroleum, Beijing (Grant No. PRP/open-1206)
文摘Firstly, a new analytical error model of the cumulative geoid height using the three-dimensional diagonal tensors of satellite gravity gradiometry (SGG) is introduced based on the variance-covariance matrix principle. Secondly, a study for the requirements demonstration on the next-generation GOCE Follow-On satellite gravity gradiometry system is developed using different satellite orbital altitudes and measurement accuracies of satellite gravity gradiometer by the new analytical error model of SGG. The research results show that it is preferable to design satellite orbital altitudes of 300 km–400km and choose the measurement accuracies of 10-13/s2 –10-15/s2 from satellite gravity gradiometer. Finally, the complementarity of the four-stage satellite gravity missions, including past CHAMP, current GRACE, and GOCE, and next-generation GOCE Follow-On, is contrastively demonstrated for precisely recovering the Earth’s full-frequency gravitational field with high spatial resolution.
基金Supported by the National Natural Science Foundation of China (Grant No. 60471001)
文摘This paper presents the field test of our first demonstration cluster with five base stations (BTS) on code division multiple access (CDMA) wireless communication in China, while each BTS was installed with a high temperature superconductor (HTS) receiver. The HTS receivers have the same centre frequency of 830 MHz, a bandwidth of 13 MHz, and a noise figure (NF) of 0.9 dB. After the conventional receivers in the BTSs were replaced by the HTS receivers, a consequent drive test was carried out. A 2.35 dB decrease of the mean mobile transmit power was observed in the demonstration cluster.