Abstract
Considering the large-scale of manned spacecraft and the increasing scope of EVA, a full-range and anti-multipath communications method for EVA is proposed to solve the problem of low coverage and severe multipath effect which cannot be solved by traditional method. Multiple antennas are evenly distributed around the manned spacecraft to ensure the full communication coverage of EVA. FDD (Frequency Division Dual) is adopted and different frequency is assigned to the forward link and backward link respectively. DS-CDMA (Direct-Sequence Code Division Multiple Access) is applied. Diverse spreading codes are distributed to each astronaut of EVA, and the problem of EVA communication interference for multiple astronauts is solved. In order to weaken the multipath effect brought by shield and reflection of manned spacecraft, a communication method by combination is proposed. Time diversity technique is applied that manned spacecraft transmits the forward message through multiple antennas in time staggered mode, and the astronaut of EVA is searching the maximum point in limited time by correlation of sliding window. The rest peaks are found near the original one, and the maximum ratio combining is carried out by the judge of peak value. Space diversity technique is also used that manned spacecraft receives the backward information of astronauts by multiple antennas, and all the peaks are found by the correlation through sliding window. The maximum ratio combining is implemented by the estimation. Simulation is made, and the result shows that by whole-scope communications method for EVA, the signal to noise ratio can be reduced 1–4 dB to realize the BER (Bit Error Rate) of 10–5 comparing with other methods, and it realize the full-range of EVA communication without interruption.
Access this chapter
Tax calculation will be finalised at checkout
Purchases are for personal use only
Similar content being viewed by others
References
Yutao Hao, Baoguo Liu, Wang Ruijun et al (2014) Research on TT&C system in international space station. Manned Spaceflight 20(2):165–172 (in Chinese)
Zhi S, Bainan Z, Teng P et al. (2009) Research and development of Shenzhou-7. Manned Spaceflight 15(2):16–21, 48 (in Chinese)
Chen Jindun, Liu Weibo, Chen Shanguang (2009) The system design and flight application of astronaut EVA in Shenzhou VII mission. Manned Spaceflight 15(2):1–9 (in Chinese)
Xiao Yu, Ma Xiaobing, Zhongqiu Gou (2010) Failure mode and countermeasure design and implement for Shenzhou spaceship’s extravehicular activity. Spacecraft Eng 19(6):56–60 (in Chinese)
Zhihao Pang (2008) Development of technologies of extravehicular activities. Sci Technol Rev 26(20):21–27 (in Chinese)
Guangchen Zhu, Shijin Jia (2009) The ground verification of spacecraft EVA functions. Manned Spaceflight 15(3):48–53 (in Chinese)
Zhou Geqiang, Xuan Yong, Zou Yongzhong (2010) Application analysis on the novel CDMA technology in extravehicular communication. Manned Spaceflight 3:14–18
Guodong Zhao, Xiaoting Chen, Liu Huijie et al (2009) Channel model of LEO satellite and high resolution rake receiver. Aerosp Shanghai 26(5):52–55
Li Miao, Lv Shanwei, Zhang Jianglin et al (2004) A novel multistage blind space-time multiple receiver for DS/CDMA. Acta Electronica Sinica 32(9):1553–1555
Zhang Lin, Qin Jiayin (2007) New efficient methods for performance analysis of maximal ratio combining diversity receivers. Chin J Radio Sci 22(2):347–350
Author information
Authors and Affiliations
Corresponding author
Editor information
Editors and Affiliations
Rights and permissions
Copyright information
© 2020 Springer Nature Singapore Pte Ltd.
About this paper
Cite this paper
Long, Y., Huang, K., Qi, X. (2020). Design of EVA Communications Method for Anti-multipath and Full-Range Coverage. In: Liang, Q., Wang, W., Liu, X., Na, Z., Jia, M., Zhang, B. (eds) Communications, Signal Processing, and Systems. CSPS 2019. Lecture Notes in Electrical Engineering, vol 571. Springer, Singapore. https://doi.org/10.1007/978-981-13-9409-6_16
Download citation
DOI: https://doi.org/10.1007/978-981-13-9409-6_16
Published:
Publisher Name: Springer, Singapore
Print ISBN: 978-981-13-9408-9
Online ISBN: 978-981-13-9409-6
eBook Packages: EngineeringEngineering (R0)