CSRH模拟接收机设计

本文叙述了日像仪实验的方案，双天线干涉仪中模拟接收机的结构，灵敏度，动态范围，噪声，增益的各级分配等问题，基于实验方案设计了日像仪模拟接收机。     

Evolution of H2O content in a polymetamorphic terrane: the Plattengneiss Shear Zone (Koralpe, Austria)

The Koralpe of the Eastern European Alps experienced high-temperature/low-pressure metamorphism (∼650 °C and 6.5 kbar) during the Permian and eclogite facies metamorphism (∼700 °C and 14 kbar) during the Eo-Alpine (Cretaceous) metamorphic event. In the metapelitic Plattengneiss shear zone that constitutes much of the Koralpe, the second metamorphism caused only partial re-equilibration of the assemblages formed during the first metamorphism. It is shown here that the Eo-Alpine mineral assemblage, garnet + biotite + muscovite + plagioclase + quartz (with or without kyanite), formed under low water activity conditions that are consistent with the level of dehydration that occurred during the Permian event. This implies that the rocks were essentially closed-system from the peak of the Permian metamorphism through the Eo-Alpine event. The evolution of water content of the rocks is traced through time: that prograde dewatering during the Permian metamorphic event terminated at the metamorphic peak with a water content around 3–4 mol.%. The water content remained then constant and led to water-undersaturation during the subsequent Eo-Alpine metamorphism. From the water content and activity evolution a post-peak isothermal decompression path close to the solidus is inferred for the Eo-Alpine event.     

基于功率和相位联合估计TLS-ESPRIT算法的极化干涉SAR数据分析

在推导各散射信号功率计算方法的基础上,提出基于功率和干涉相位联合估计的TLS-ESPRIT方法。因为干涉图像中的各主散射波和干涉相位能被分别估计,所以该算法可以利用同一分辨单元中不同散射机制后向散射信号功率的不同,将干涉相位分类实现散射中心分离。该方法通过提取两个占优势的相位得到两个高度,从而分别检测出森林的植被层和地表,特别是当散射波不相关并有不同的极化特性时,该方法有较好的性能,从而提高植被高度参数的估计精度。详细阐述该方法的原理和实施步骤,并通过对SIR-C/X-SAR的L波段实际数据进行分析处理,验证算法的有效性。     

基于酉ESPRIT算法的极化干涉相位估计

目前SAR极化干涉测量地形参数已经成为一种新兴的前沿技术。在现有提取极化干涉相位的技术中,由空间谱估计理论发展而来的,利用MUSIC、TLS-ESPRIT算法获取干涉相位信息的方法正逐步完善起来。但由于SAR信号存在散射点的观测数据少的问题,利用上述方法往往不能得到更高精度的干涉相位。作者提出的基于酉ESPRIT算法估算干涉相位的方法,充分利用了复观测数据以及共轭数据中的信息,使得观测数据等效增加了一倍,从而提高了植被高度参数的估计精度。本文详细阐述了该方法的原理和实施步骤,并通过对SIR-C/X-SAR的L波段实际数据进行验证处理,表明酉ESPRIT算法十分有效。     

川江航道BDS/GNSS船舶精密位速监测性能分析

采用精密单点定位和相位历元间差分法分别评估普通航段和库区航段BDS/GNSS的定位和测速性能。结果表明,在普通航段,BDS-2定位精度为0.1~0.2 m;GPS、BDS-3、BDS全系统的定位精度相对较高,水平方向优于0.07 m,垂直方向优于0.09 m,测速精度相当,均在mm/s级;BDS/GPS、GPS/GLONASS/BDS/Galileo组合后,定位和测速精度相较于单系统提升约30%。在库区航段,GPS定位精度严重下降,水平方向为0.6 m;BDS-3与BDS全系统定位精度略有下降;多系统组合后,定位和测速精度受周围环境影响程度较低,与普通航段基本相当。     

HY-2B星载GPS数据质量及简化动力学精密定轨分析

对HY-2B卫星星载GPS数据进行质量检查,分析伪随机脉冲先验值对简化动力学精密定轨的影响。结果发现,在所有时间间隔中,先验标准差为1×10^-8 m/s²时定轨精度最高,最优伪随机脉冲时间间隔为6 min。估计天线相位中心变化（PCV）,分析不同分辨率（10°×10°、5°×5°）PCV模型对定轨结果的影响,并使用载波相位残差、重叠轨道比较和SLR检核对定轨结果进行检验。结果表明,99%以上的历元能观测到4颗以上GPS卫星,数据完整率达到99.65%,L1、L2波段的多路径误差RMS均值分别为15.7 cm、9.5 cm,证明HY2国产接收机性能良好。轨道内符合精度均达到cm级;未加PCV模型时,SLR检核RMS值为27.8 mm,加入10°×10°、5°×5° PCV模型后,SLR检核RMS值分别提高0.9 mm和1.2 mm,说明轨道外符合精度也达到cm级。     

北斗三号卫星天线相位中心改正模型对精密定轨和定位的影响

基于实测数据分析天线相位中心PCO改正模型和观测值频点选择对北斗三号卫星精密定轨和定位的影响。结果表明,基于北斗官方CSNO发布的PCO模型定轨定位表现稍优于IGS协议模型。此外,相较于两者PCO模型差异的影响,B1C/B2a与B1I/B3I观测值频点的选择对精密定位影响更为显著。以IGS B1I/B3I PCO模型为参考,CSNO B1C/B2a PCO模型定位坐标在E、N、U方向上的精度分别提升约5%、13%、14%,可应用于北斗高精度数据处理。     

地磁逐日比异常电磁学成因的进一步分析

基于地磁逐日比异常期间地磁垂直分量日变化幅度变大或变小的统计结果,发现地磁逐日比高值异常是由异常日的地磁垂直分量日变化幅度变小和异常前一天的日变化幅度变大所致。其中,异常日的日变化幅度变小可能是地磁逐日比异常的主要因素,但异常前一天的日变化幅度变大也是异常成立的重要因素。此外,引用前人感应电流假说,结合统计结果进行了机理解释,研究结论进一步证实了前人对该方法的机理推测。     

BZ油田沙二段低渗储层定量预测方法

BZ油田沙河街组低渗储层埋藏深、钻井少、地震资料品质差、相带变化快,储层展布特征认识不清,直接制约油田开发调整及滚动挖潜。针对这一难点,在储层特征、地震资料品质分析基础上,结合井震标定、正演模拟分析,探讨了90°相位转换技术在BZ油田沙二段低渗储层预测中的适用性。结果表明,BZ油田沙二段1—4小层砂层组厚度与地震资料分辨最佳厚度匹配较高,90°相位转换地震剖面中地震零相位反射界面与砂层组岩性界面对应关系好,正演波形能够定量刻画砂层组纵向厚度;基于90°相位转换技术,在砂层组厚度定量表征基础上,运用地震沉积学方法和统计学方法,实现了BZ油田沙二段主力含油层段砂体厚度的定量预测,新增调整井实钻储层厚度与钻前预测基本一致。该研究成果有效指导了BZ油田沙二段低渗油藏整体开发方案的部署和实施,也可为类似区块勘探开发提供借鉴。     

Production of Potash and N-Mg Compound Fertilizer via Mineral Shoenite from Kunteyi Salt Lake: Phase Diagrams of Quaternary System(NH_4)_2SO_4-Mg SO_4-K_2SO_4-H_2O in the Isothermal Evaporation and Crystallization Process

Based on the requirement of the new technology for producing potassium sulfate and N-Mg compound fertilizer,boussingaultite,by the reaction of the mineral shoenite from Kunteyi Salt Lake,Qinghai province,and the industrial byproduct ammonium sulfate,the solubilities of the quaternary system (NH_4)_2SO_4-Mg SO_4-K_2SO_4-H_2O at 25.0oC in the isothermal evaporation and crystallization process were measured using the isothermal evaporation method,and the corresponding phase diagrams were plotted.According to the diagram,this system contains six saturation points and six solid phase fields of crystallization,which correspond to (K_(1-m),(NH_4)_m)_2SO_4,(NH_4)_2SO_4·Mg SO_4·6H_2O,K_2SO_4·Mg SO_4·6H_2O,Mg SO_4·6H_2O,(K_(1-n),(NH_4)_n)_2SO_4·Mg SO_4·6H_2O and Mg SO_4·7H_2O,respectively.By analyzing and calculating the isothermal evaporation and dissolution phase diagram of this quaternary system at 25.0oC,K_2SO_4 and (NH_4)_2SO_4·Mg SO_4·6H_2O can be separated via K_2SO_4·Mg SO_4·6H_2O and (NH_4)_2SO_4 as raw materials.Theoretical calculations about the proposed process were carried out and verified by experiment,which indicated that the yield of potassium sulfate was improved and the magnesium resources were fully utilized.