分类: 地球科学 >> 空间物理学 提交时间: 2017-03-10
摘要: In order to satisfy a relatively high resolution for the retrieval of snow water equivalent, an X/Ku-band dual-frequency full-polarized SCATterometer (DFPSCAT) onboard Water Cycle Observation Mission (WCOM) satellite is designed for high-resolution observations. However, given the following situations, the method called “rotating azimuth Doppler discrimination” is proposed, which can satisfy the resolution requirement and real-time processing: 1) the conically rotation rate of antenna is relatively fast; 2) the swath width is larger than 1000 km; and 3) day or night observation capabilities are required. Considering the complexity of the system's design and the improvement of azimuth resolution capability, a burst pulsing scheme is addressed to satisfy the numbers of azimuth sampling. The simulation model is used to analyze the feasibility of azimuth discrimination method based on geometry and system parameters. It is shown that the achievable azimuth resolution is about 2–5 km at far end of the swath and only 5km at near end of the swath. The results show that when the size of a slice is set as 2–5 km, the Kpcis about less than 0.4 as snow depth varies, and the Kpcof combined slices is smaller than a single slice.
分类: 地球科学 >> 空间物理学 提交时间: 2016-05-03
摘要: In order to satisfy a high resolution for the measurement of snow water equivalent, we use the system of using the dual frequency(X-band 9.6GHz and Ku-band 17GHz) and full polarization. This paper discusses the various system options(scanning pencil-beam, high PRF, high SNR) and tradeoffs considered for improving the azimuth resolution of scatterometer are required.
分类: 地球科学 >> 空间物理学 提交时间: 2016-05-03
摘要: Ocean surface current is a very important parameter of ocean dynamic environment, which has been connected to global climate change, marine environment forecasting, marine navigation, engineering security and so on. Doppler scatterometer is a new type of scatterometer that can be used to measure ocean surface current as well as the ocean wind vector in space. The Doppler Scatterometer is based on a real aperture radar, which can achieve a very wide swath. It can provide the ocean surface current and wind vector information in a certain resolution and achieve global coverage quickly, which is very important for the marine environment forecasting and climate changes research.