Ruwisch Fabian, Jain Ankit, Schön Steffen
Institut für Erdmessung (IfE), Leibniz Universität Hannover, 30167 Hannover, Germany.
Sensors (Basel). 2020 Jul 21;20(14):4046. doi: 10.3390/s20144046.
We present analyses of Global Navigation Satellite System (GNSS) carrier phase observations in multiple kinematic scenarios for different receiver types. Multi-GNSS observations are recorded on high sensitivity and geodetic-grade receivers operating on a moving zero-baseline by conducting terrestrial urban and aerial flight experiments. The captured data is post-processed; carrier phase residuals are computed using the double difference (DD) concept. The estimated noise levels of carrier phases are analysed with respect to different parameters. We find DD noise levels for L1 carrier phase observations in the range of 1.4-2 mm (GPS, Global Positioning System), 2.8-4.6 mm (GLONASS, Global Navigation Satellite System), and 1.5-1.7 mm (Galileo) for geodetic receiver pairs. The noise level for high sensitivity receivers is at least higher by a factor of 2. For satellites elevating above 30 ∘ , the dominant noise process is white phase noise. For the flight experiment, the elevation dependency of the noise is well described by the exponential model, while for the terrestrial urban experiment, multipath and diffraction effects overlay; hence no elevation dependency is found. For both experiments, a carrier-to-noise density ratio (C/N 0 ) dependency for carrier phase DDs of GPS and Galileo is clearly visible with geodetic-grade receivers. In addition, C/N 0 dependency is also visible for carrier phase DDs of GLONASS with geodetic-grade receivers for the terrestrial urban experiment.
我们针对不同类型的接收机，在多种运动场景下对全球导航卫星系统（GNSS）载波相位观测值进行了分析。通过开展地面城市和空中飞行实验，在移动零基线的高灵敏度和大地测量级接收机上记录多GNSS观测值。对采集到的数据进行后处理；利用双差（DD）概念计算载波相位残差。针对不同参数分析了载波相位的估计噪声水平。我们发现，对于大地测量接收机对，L1载波相位观测的双差噪声水平在1.4 - 2毫米（GPS，全球定位系统）、2.8 - 4.6毫米（GLONASS，全球导航卫星系统）和1.5 - 1.7毫米（伽利略）范围内。高灵敏度接收机的噪声水平至少高出2倍。对于仰角高于30°的卫星，主要噪声过程是白相位噪声。对于飞行实验，噪声的仰角依赖性可以用指数模型很好地描述，而对于地面城市实验，多径和衍射效应叠加；因此未发现仰角依赖性。对于这两个实验，使用大地测量级接收机时，GPS和伽利略载波相位双差的载噪比（C/N₀）依赖性清晰可见。此外，在地面城市实验中，使用大地测量级接收机时，GLONASS载波相位双差的C/N₀依赖性也可见。
