Conformal Window Glass Automotive Active FM Antennas

With the rapid development of automobile industry, it is challenging to satisfy the mechanical, aesthetic, electromagnetic, and communicational requirements of today’s modern car manufacturers and owners. During recent years, extensive development of wireless communication technologies has resulted in innovative services and devices which are now utilized in modern vehicles. It is well known that the antenna is the essential element and plays a vital role in wireless communication systems. In order to meet a variety of communication needs, modern cars may contain multiple antennas that affect the aesthetics of the car. Conformal antenna with its own merits is favored by the vehicle manufactures. It is conformal with the car, without the destruction of the vehicle’s overall appearance. Therefore, it is valuable to research and to design the conformal window glass automotive active FM antennas.In comparison with the whip antenna, automotive passive antenna has a more directional FM radiation pattern. To overcome such performance distortions, a well known technique called space diversity is utilized to improve the signal reception. In addition, automotive passive antenna exhibits lower FM gain. Low noise amplifiers are used that can amplify extremely weak signals with minimal added noise, providing the signal-to-noise ratio of the system at a predetermined required level. In this paper, a low noise amplifier and two FM passive antennas are designed for Shenyang Sunpool Automotive Electronics Co., Ltd.The preliminary design of low noise amplifier is based on theory. And ADS (the development of Agilent) is used to simulate and optimize. Finally, the fabricated and soldered LNA is tested with Vector Network Analyzer and Noise Figure Analyzer. For the best performance of LNA, the process of simulation-fabrication-test is repeated.Based on the conventionalλ/4 monopole, automotive FM passive antenna is designed. With the help of FEKO (the development of EMSS), the shape and the size of antenna are optimized. Consequently, the antenna which is fabricated and modified in the laboratory meets the design requirements.