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The integration of GPS with GLONASS may be considered a major milestone in satellite-based positioning, because it can dramatically
improve the reliability and productivity of said positioning. However, unlike GPS, GLONASS satellites transmit signals at
different frequencies, which result in significant complexity in terms of modeling and ambiguity resolution for integrated
GPS and GLONASS positioning systems. In this paper, a variety of mathematical and stochastic modeling methodologies and ambiguity
resolution strategies are analyzed, and some remaining research challenges are identified. The exercise, of developing mathematical
models and processing methodologies for integrated systems based on more than one satellite system, is a valuable one as it
identified crucial issues concerned with the combination of any two or more microwave positioning systems, be they satellite-based
or terrestrial. Hence these are experiences that can be applied to future projects that might integrate GPS with Galileo,
or GLONASS and Galileo, or all three. ? 2001 John Wiley & Sons, Inc. 相似文献
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In this paper the differences between Meiyu and Baiu front in 1983 have firstly been analysed, the trajectories of air on and to the north side of Meiyu and Baiu fronts during the Meiyu period have then been traced, and the fore-casting and simulating of 4 sets of Meiyu onset of the year have finally been run utilizing the global model at UK Me-teorological Office. The results show: 1) Meiyu fronts are different from Baiu ones in temperature, humidity and stratification fields in lower atmosphere; and the possibly reasons for it are explained. 2) The Bay of Bengal is the main moisture source for Meiyu front, the South China Sea and the Pacific, for Baiu ones; and some existed argu-ments on it are also discussed. 3) The onset of Meiyu and its rainfall and rain belts are sensitive to the Tibetan Plateau, and the water vapour conditions over the Bay of Bengal and the South China Sea, but not sensitive to the SST over the equatorial area or to the East of Japan. 相似文献
717.
Mike Kirkby 《地球表面变化过程与地形》1991,16(2):181-181
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