Automobile Laminated Glass Window Embedded Transmitarray and Ray Tracing Validation for Enhanced 5G Connectivity

This article presents a 38.5 GHz transmitarray, for the first time, embedded into laminated car glass, and indoor 5G connectivity enhanced by this transmitarray laminated glass has also been validated using a ray-tracing simulator. The transmitarray structure reduces the penetration loss and realizes a desired beam shaping function. Metallic layers of the transmitarray structure adopt the Jerusalem cross shape that minimizes opacity. A ray-tracing simulator was used to analyze electromagnetic fields in a massive space, such as the interior of a car. The proposed transmitarray laminated glass was applied to the passenger side window in the simulation, and the variation in the communication performance with and without the transmitarray was compared. This comparison confirmed that field intensity increases of up to approximately 5 dB are realized at the target area, where communication is mainly performed. In addition, the proposed transmitarray laminated glass increases the field intensity by more than 3 dB, from approximately 36 to 40 GHz. The transmitarray laminated glass has also been fabricated. The maximum field intensity increase of approximately 5 dB, which is similar to the simulation results, was successfully measured at the target area.