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Bias elimination in tracking with converted position and Doppler measurements
2012 IEEE 51st IEEE Conference on Decision and Control (CDC), 2012In target tracking, it is natural to describe target motion in Cartesian coordinates. In many cases the measurements require some form of nonlinear conversion prior to use in a Cartesian coordinate tracker. There are two sources of bias that can arise as a result of this conversion.
Steven V. Bordonaro +2 more
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Doppler-Aided Algorithm for BeiDou Position
2013Real-time GNSS positioning rely mainly on pseudorange and carrier-phase. The pseudorange is not accurate because of a lot of noise and interference in environment. High-precision carrier-phase used to smooth pseudorange. While, when cycle slip occurs, the carrier-phase measurement is bias.
Dengyun Lei, Weijun Lu, DunShan Yu
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Research on A-GPS Rapid Positioning Algorithm Based on Doppler Positioning
2014The time to first fix (TTFF) of conventional GPS receiver need one minute or more in the case of autonomous cold start, when in weak signal environments like indoors or urban canyons, even tens of minutes are difficult to achieve the TTFF. Assisted Global Positioning System provided ephemeris, a priori time and a priori position for a A-GPS receiver ...
Zhiyong Huang +3 more
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Improvement of GPS position estimation using SNR and Doppler
2017 IEEE International Conference on Advanced Intelligent Mechatronics (AIM), 2017In this paper, we propose a method to improve the accuracy of GPS positioning in the environment where the satellite signal including error information is excluded and the satellite signal is reflected and distorted like urban area. Factors that degrade GPS positioning accuracy include time error, ionospheric error, tropospheric error, and multipath ...
Jong-woo An, Jang-Myung Lee
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Doppler radar sensor positioning in a fall detection system
2012 Annual International Conference of the IEEE Engineering in Medicine and Biology Society, 2012Falling is a common health problem for more than a third of the United States population over 65. We are currently developing a Doppler radar based fall detection system that already has showed promising results. In this paper, we study the sensor positioning in the environment with respect to the subject.
Liang Liu 0014 +4 more
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Statistical techniques and Doppler satellite positioning
Philosophical Transactions of the Royal Society of London. Series A, Mathematical and Physical Sciences, 1980Abstract Two problems are addressed: (a) the detection of outliers in (Doppler satellite) observations, and (b) the testing of coordinates in (Doppler satellite) networks. In both problems, confidence regions of the ‘out of context’ and ‘within context’ varieties are developed, and it is shown that the latter are in general about 1 1 ...
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An Anti-spoofing Method Based on Doppler Positioning
The International Technical Meeting of the The Institute of Navigation, 2017The vulnerability of GNSS to spoofing attacks has received much attention in recent years. Among various spoofing techniques, replay attack is a typical and common one due to its simplicity and effectiveness. To detect and mitigate spoofing threats including the replay spoofing, a new anti-spoofing method is proposed.
Fengkui Chu +4 more
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Triatomic Hydrogen and Doppler Effect in Hydrogen Positive Rays
Nature, 1947J. J. THOMSON1 discovered the triatomic molecule of hydrogen by the positive ray parabolic method. It was later confirmed by Dempster2, Duane and Wendt3, and several others. Its occurrence is very frequently noted in discharge tubes, but the optimum conditions are not well defined. While investigating the Doppler effect in hydrogen positive rays, using
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GPS Doppler Processing for Precise Positioning in Dynamic Applications
Navigation, 1985A doppler processing technique for smoothing the GPS code-phase measurements is presented. It is shown that this technique can enhance the resolution of C/A pseudo-range measurements to better than 1 centimeter. Data is presented to show that it is possible to obtain position fixes with an runs scatter of a few centimeters from the C/A code.
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Possibilities and Limitations of Doppler Positioning in Geodynamics
1979During the past years Doppler positioning by aid of artificial satellites, especially within the US Navy Navigation System, has been introduced into large fields of geodesy. This new technique nowadays is used to determine control points especially in countries where we have no unique first order triangulations, to combine national geodetic networks ...
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