A rapid detection method for NLOS signals based on the vehicle mounted camera

Non-line-of-sight (NLOS) signals seriously impact the satellite positioning results in the urban canyons, causing errors of up to a hundred of meters. To rapidly detect NLOS signals in urban areas, this paper introduces a detection method based on vehicle mounted camera. First, all the satellites are projected as error ellipses on the camera image. Then, the trained Fisher discriminant method is used to determine whether the image within the error ellipse is the sky or not, which in turn enables NLOS detection. The experimental results demonstrate that the method efficiently detects NLOS signals, thereby enhancing positioning accuracy.