【摘 要】
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OFDM signal systems have been widely used in mobile communications,digital satellite TV,and provided higher transmission rate and positioning information service.It has the potential in timing and Ran
【机 构】
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National University of Defense Technology, Deya road 109,410073 Changsha, China
论文部分内容阅读
OFDM signal systems have been widely used in mobile communications,digital satellite TV,and provided higher transmission rate and positioning information service.It has the potential in timing and Ranging.Since limitation of GNSS signal strength,indoors,underground and in the other scenes,CDMA-based GNSS signal receiver sensitivity cant meet the requirements,or serious in multipath influence,and poor in positioning accuracy.Satellite navigation posi-tioning system based on ranging and transmission with OFDM is still a hot issue in the future.Satellite navigation and positioning is also facing with new opportunities and challenges.Methods based on existing OFDM timing& ranging technology are analyzed,which points out synchronization algorithm and channel estimation is the key to enhance accuracy.On the basis,this paper proposes three aspects of OFDM to enhance the accuracy: ① Combination of a variety of signal system;② improving 2πlimitation of TOA phase measurements in the frequency domain;③ Accurate channel estimation utilizing OFDM signal.
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