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Localization using GNSS alone may cause relatively large errors due to problems such as multipath and satellite visibility especially in urban areas compared to open areas. Many techniques for improving position accuracy using ADAS sensors such as cameras and Lidar were studied. In case of camera, performance decreases due to external environment such as illuminance is problematic, whereas the algorithm using Lidar is relatively robust to external factors, having less performance degradation than camera. V2X is ideally suited to obtain the navigation information of the surrounding objects. In this paper, we propose a localization method using the information of the surrounding objects acquired with V2X which can know the position in the navigation coordinate system and the Lidar which can know the relative position in the coordinate system of the center of the user's vehicle. Simulation results obtain by using a real-time driving simulator are included in the paper to show the performance of the proposed methods.

This paper presents an adaptive Kalman filter approach to track scintillating GNSS signals based on the empirical knowledge on the signal-to-noise ratio. The adaptive scheme to adjust the Kalman filter gain, changing in time-varying optimal manner for different C/N 0 to have different equivalent noise bandwidths, is employed to track the signal in deep amplitude fades under strong ionospheric scintillations.

This paper presents a preliminary result of the effectiveness study on vector-tracking-loop for different signal fading effects for different satellite signals in analytical way. In order for this, we use a simple model with a constant pseudorange measurement covariance for all satellites available in channels. After then, we expand the result to the general case of signal fading where only several satellites are impaired by fading effect. Moreover, we define Geometry-related Range Accuracy Coefficient (GRAC) based on the covariance matrix of pseudorange residuals in vector-tracking. This coefficient can be used in calculating the available signal-to-noise ratio gained by the vector-tracking. The off-diagonal elements of the covariance matrix of pseudorange residuals are interpreted as effective interaction between channels to share the contained information with others. A preliminary numerical simulation was performed to analyze the impact of each element of the covariance matrix to the overall system.