The reliability and performance of GPS receivers depend on the quality of the signal received, which can be largely affected by the interference caused by buildings, trees, and other obstacles. Since obstacles are always present in practical applications, several statistical representations have been developed along the years to measure, predict, and compensate errors induced by interferences. Two of the most used models to characterize GPS signal fading are the Nakagami-m and Rice, but in this work, we present evidence that supports the κ–μ distribution as the best fit to deal with multifrequency GPS multipath channels inside urban, rural, and forest areas. A synthetic signal simulator was developed to create propagation cases involving scattering clusters and specular reflections. Additionally, experimental measurements are presented to confirm the κ–μ distribution as the best distribution to characterize different situations on the available three GPS frequencies. We then present typical values of fading coefficients in L1, L2C, and L5 signals, for cases involving urban canyons, regular urban, rural, and dense vegetation areas. These coefficients can also be used to evaluate the receiver performance under similar cases or may be applied in weights measurement methods for positioning computation improvement.

GPS接收机的可靠性和性能取决于所接收信号的质量，而建筑物，树木和其他障碍物所造成的干扰会极大地影响GPS接收机的质量。由于在实际应用中总是存在障碍，因此多年来，已经开发出了几种统计表示形式，以测量，预测和补偿由干扰引起的误差。最常用的模型的两个表征GPS信号的衰落是Nakagami-米和大米，但在这项工作中，我们提出证据支持κ - μ分布最适合处理城市，农村和森林地区的多频GPS多径通道。开发了一种合成信号模拟器来创建涉及散射簇和镜面反射的传播情况。此外，还进行了实验测量，以确认κ – μ分布是在可用的三个GPS频率上表征不同情况的最佳分布。然后，对于涉及城市峡谷，常规城市，农村和茂密植被区的情况，我们将给出L1，L2C和L5信号中衰落系数的典型值。这些系数也可以用于评估类似情况下的接收机性能，或者可以应用于权重测量方法中以改善定位计算。