A Novel Method for Characterizing Atmospheric Turbulence Using Global Positioning System (GPS)

使用全球定位系统 (GPS) 表征大气湍流的新方法

• 批准号: 0222531
• 负责人: Pedro Elosegui
• 金额: $ 8.81万
• 依托单位: Smithsonian Institution Astrophysical Observatory
• 依托单位国家: 美国
• 项目类别: Standard Grant
• 财政年份: 2002
• 资助国家: 美国
• 起止时间: 2002-09-01 至 2004-08-31
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=0222531&HistoricalAwards=false
• 关键词: Novel; Method; Characterizing; Atmospheric; Turbulence

Signals from Global Positioning System (GPS) satellites propagate through the atmosphere with a velocity determined by the refractivity of the air, which depends on temperature, pressure, and humidity. This award supports research based on the principle that the difference between the propagation delays from two GPS satellites measured at the same position on the ground depends on the difference in the integrated refractivity along the two ray paths. The propagation delays are calculated from the measured phases of the GPS signals and are subject to uncertainty because of clock errors, uncertainties in satellite range, and receiver noise. However, short-term fluctuations of the phase difference about averages over periods from a few seconds to minutes are largely free of these uncertainties and depend mainly on changes in the path-average refractivity. These fluctuations are caused by the variability of atmospheric structure and hence may be regarded as a measure of the irregularity, or turbulence. The objective of the work is to evaluate the feasibility of continuous, accurate, all-weather remote sensing of turbulence by monitoring GPS signals. It holds the potential of improving weather forecasts and alleviating aviation hazards through better understanding of the occurrence and distribution of turbulence.

来自全球定位系统（GPS）卫星的信号在大气中传播，其速度由空气的温度、压力和湿度决定。 该奖项支持基于以下原理的研究：在地面相同位置测量的两颗GPS卫星的传播延迟之间的差异取决于沿两条射线路径沿着的综合辐射活动的差异。 传播延迟是从GPS信号的测量相位计算的，并且由于时钟误差、卫星范围的不确定性和接收机噪声而受到不确定性的影响。 然而，从几秒到几分钟的平均值的相位差的短期波动在很大程度上不受这些不确定性的影响，主要取决于路径平均活动的变化。 这些波动是由大气结构的变化引起的，因此可以被视为不规则性或湍流的量度。 这项工作的目的是评价通过监测全球定位系统信号对湍流进行连续、准确、全天候遥感的可行性。 它具有通过更好地了解湍流的发生和分布来改进天气预报和减轻航空危险的潜力。