The Shen Zhou Institute, a subsidiary of CAST, signed an educational resources exchange and cooperation agreement with Aeronautics and Space Institute （IAS） of France in early June. 2006. IAS Managing Director Miche...The Shen Zhou Institute, a subsidiary of CAST, signed an educational resources exchange and cooperation agreement with Aeronautics and Space Institute （IAS） of France in early June. 2006. IAS Managing Director Michel Reynes paid a return visit to the Shen Zhou Institute on June 30 and negotiated details of the joint education program.展开更多
China Academy of Space Technology （CAST） held a meeting for seed breeding satellite recently. Participants reviewed the technical status and development plan of China＇s first seed breeding satellite. The assembly ...China Academy of Space Technology （CAST） held a meeting for seed breeding satellite recently. Participants reviewed the technical status and development plan of China＇s first seed breeding satellite. The assembly and tests of the satellite will be conducted in fill wing, which means China＇s first breeding satellite will be launched in 2006.展开更多
The absolute delay caused by equipment of radio navigation satellite service (RNSS) signal channel must be calibrated in the application of positioning. The measurement accuracy of absolute delay will affect the posit...The absolute delay caused by equipment of radio navigation satellite service (RNSS) signal channel must be calibrated in the application of positioning. The measurement accuracy of absolute delay will affect the positioning precision of RNSS user. An absolute delay measurement technique using digital envelope detection was developed for RNSS signal transmission channel. The RNSS transmission signal of navigation satellite and the one pulse per second (1PPS)generated by satellite time keeping system were sampled synchronously. With sampling data of 1PPS,the reference point of the absolute delay can be decided at first,and then sampling data of RNSS transmission signal were truncated. The truncated data were processed using digital envelop detection algorithm to search the phase converting points of RNSS signal. Finally,the absolute delay of RNSS signal transmitting channel was calculated. Uncertainty of measurement with proposed technique is lower than 0. 2 ns as the sampling frequency is 10 GHz.展开更多
文摘The Shen Zhou Institute, a subsidiary of CAST, signed an educational resources exchange and cooperation agreement with Aeronautics and Space Institute （IAS） of France in early June. 2006. IAS Managing Director Michel Reynes paid a return visit to the Shen Zhou Institute on June 30 and negotiated details of the joint education program.
文摘China Academy of Space Technology （CAST） held a meeting for seed breeding satellite recently. Participants reviewed the technical status and development plan of China＇s first seed breeding satellite. The assembly and tests of the satellite will be conducted in fill wing, which means China＇s first breeding satellite will be launched in 2006.
基金National Science and Technology Major Project of China(No.DHZX01A02004)
文摘The absolute delay caused by equipment of radio navigation satellite service (RNSS) signal channel must be calibrated in the application of positioning. The measurement accuracy of absolute delay will affect the positioning precision of RNSS user. An absolute delay measurement technique using digital envelope detection was developed for RNSS signal transmission channel. The RNSS transmission signal of navigation satellite and the one pulse per second (1PPS)generated by satellite time keeping system were sampled synchronously. With sampling data of 1PPS,the reference point of the absolute delay can be decided at first,and then sampling data of RNSS transmission signal were truncated. The truncated data were processed using digital envelop detection algorithm to search the phase converting points of RNSS signal. Finally,the absolute delay of RNSS signal transmitting channel was calculated. Uncertainty of measurement with proposed technique is lower than 0. 2 ns as the sampling frequency is 10 GHz.
