• 主题
高级搜索  >
历史搜索 清空历史
首页> 外文会议>4th ESA International Conference on Spacecraft Guidance, Navigation and Control Systems, 4th, Oct 18-21, 1999, ESTEC, Noordwijk, The Netherlands >ATTITUDE DETERMINATION USING GPS: MULTIPATH REDUCTION THROUGH GPS ANTENNA DESIGN
【24h】

ATTITUDE DETERMINATION USING GPS: MULTIPATH REDUCTION THROUGH GPS ANTENNA DESIGN

机译：使用GPS进行姿态确定：通过GPS天线设计进行多路径缩减

获取原文
获取原文并翻译 | 示例
页面导航
  • 摘要
  • 著录项
  • 相似文献
  • 相关主题

摘要

Multipath is recognised as the performance driver for GPS-based attitude determination, so that multipath reduction and mitigation is the key to significantly improve the achievable accuracy, today experimentally demonstrated to about 0.2 to 0.4 deg. RMS. Being a slowly-varying bias with time constants determined by spacecraft dynamics relative to the GPS constellation, multipath filtering appears operationally hardly feasible. Multipath calibration is a promising avenue, but requires an independent and accurate attitude reference if to be performed on-orbit. This paper is therefore focused on the third major class of solutions, the reduction of multipath at antenna level, by experimental investigation of alternatives to the conventional GPS patch antenna. Indeed, one of the main conclusions of the experimental assessment of GPS-based attitude determination is that the major error source is the so-called "intrinsic multipath" of the GPS antennas, caused by the mismatch between antenna diagrams. Patch antennas, widely used for GPS applications, were recognised as poor candidates for accurate attitude determination because of the large dependence of the antenna diagram to the geometry of the supporting plate (in fact patch antennas do not work properly if not attached to a sufficiently large conductive plate). As a consequence, large "edge effect" were observed, resulting in multipath-like error of several tens of mm, about the same level of actual multipath obtained when large obstacles were implemented on the plate. This paper compares test results & attitude determination performance of conventional GPS patch antennas to those obtained with alternate types of antennas with reduced dependence to the supporting plate. The first investigated antennas are 4-wire helical antenna prototypes derived from classical S-band TTC antennas, implemented at the corners of a 1.2 X 1.2 m plate installed on a building roof. Very significant performance improvements compared to patches (30%) have been demonstrated during this test campaign, yet smaller than expected from multipath predictions through detailed RF simulations. The most probable source of this discrepancy between predictions & tests was found in an artefact of the test set-up, the "external" multipath introduced by parasitic reflections on distant obstacles, allowing to expect further improvements in real space environment.
机译：多路径被公认为是基于GPS姿态确定的性能驱动因素，因此多路径的减少和缓解是显着提高可达到的精度的关键，如今已通过实验证明其约为0.2至0.4度。均方根值作为一种随时间变化的偏差，其时间常数由航天器相对于GPS星座的动力学决定，因此多径滤波在操作上似乎不可行。多径校准是一个有前途的途径，但是如果要在轨道上进行，则需要一个独立且准确的姿态参考。因此，本文将通过实验研究常规GPS贴片天线的替代方法，着眼于第三大类解决方案，即在天线级别减少多径。实际上，基于GPS的姿态确定的实验评估的主要结论之一是，主要误差源是GPS天线的所谓“本征多径”，这是由天线图之间的不匹配引起的。由于天线图对支撑板的几何形状的依赖性很大，因此广泛用于GPS应用的贴片天线被认为是确定精确姿态的较差的选择（实际上，如果未将贴片天线连接到足够大的天线，则贴片天线无法正常工作）导电板）。结果，观察到大的“边缘效应”，导致数十毫米的多径样误差，大约与在板上设置大障碍物时获得的实际多径水平相同。本文将常规GPS贴片天线的测试结果和姿态确定性能与使用其他类型的天线获得的结果进行了比较，并减少了对支撑板的依赖性。首先研究的天线是从经典S波段TTC天线衍生而来的4线螺旋天线原型，安装在建筑物屋顶上的1.2 X 1.2 m平板的角上。在测试过程中，已证明与补丁相比，性能有非常显着的提高（30％），但比通过详细的RF仿真进行的多径预测所期望的要小。在测试设置的伪像中发现了预测与测试之间这种差异的最可能原因，即对遥远障碍物的寄生反射引入的“外部”多径，从而有望在实际空间环境中得到进一步改善。

著录项

相似文献

  • 外文文献
  • 中文文献
  • 专利
获取原文

客服邮箱：kefu@zhangqiaokeyan.com

京公网安备：11010802029741号 ICP备案号：京ICP备15016152号-6 六维联合信息科技 (北京) 有限公司©版权所有

  • 客服微信

  • 服务号