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In the near future, the Ground Based Augmentation System (GBAS) is intending to provide navigation service for aircrafts and vehicles operation in apron, which requires more stringent navigation performance. The artificial structures in airport will affect the characteristics of signal in space of GBAS Very high frequency Data Broadcast (VDB) transmitter. In order to evaluate their effects on the performance of GBAS VDB, path loss of VDB signal propagating in airport must be analyzed. In cylindrical coordinates, the three dimension (3D) Parabolic Equation (PE) method combing with grid tessellation is proposed to predict GBAS VDB signal propagation path loss in airport. This method can take the lateral propagation effects into consideration and achieve a uniform solution resolution in all azimuths along the radical direction. Simulation results demonstrate the efficiency and numerical stability of this method.

Precise and robust localization is an essential factor for the guidance of vehicles driving in the airport in low visibility operation. Ground Based Augmentation System (GBAS) solution can provide satisfactory positioning in open areas, however, its performance suffered in apron area due to the effects of multipath. In order to have safe and efficient localization for vehicles, a multi-navigation data fusion algorithm is employed by using Kullback-Leibler Divergence (KLD) metric, we show how to combine GBAS and other sensory information to acquire more reliable localization. Simulation results indicate the accuracy and robustness of the proposed method.

Low pass filters are useful and necessary for direct conversion GNSS SDR, which is reconfigurable for multi-band navigation satellite systems. This paper addresses a novel low pass filter optimal design methodology, which using hybrid Taguchi and particle swarm optimization (PSO). In the optimization process, the Taguchi method is utilized to overcome the premature convergence and stagnation problem of PSO. A comparison of simulation results reveals the method’s efficiency as well as its numerical stability.

There is a certain difference between the RDH obtained from the flight inspection and the TCH calculated from geometry terrain. The problem is always neglected and someone attribute the cause of poor RDH to equipment issues, actually equipment is a problem, but the electromagnetic environment is also a very important factor overlooked by owner. When the electromagnetic environment around glide path antenna is worse, the difference of TCH and RDH is even larger, and even cannot meet the requirements for safe operation. This article study the calculation method of the actual measured RDH, revealing fundamental reason of the difference, and further explaining the importance of protecting the electromagnetic environment of the instrument landing system,.providing analysis ideas and solutions for equipment construction and maintenance engineers.

To support Differentially Corrected Positioning Service (DCPS) in airport, the Global Navigation Satellite System (GNSS) receiver’s anti-multipath ability should be validated carefully to airport environment. This paper discusses the quantification of GNSS signal characteristics in airport based on Finite Difference Time Domain-Parabolic Equation (FDTD-PE) method. The proposed method can deal with complex environment with different objects and large scale clear space of airport efficiently. An equivalent process is introduced to deal with the problem of non-uniform sampling grid. By comparing with FDTD method, the validation of this method is proved. The simulation results demonstrate the effectiveness and accuracy of this method for predicting the GNSS signal propagation in airport environment.