In this paper, the design of a miniature antenna dedicated to the detection of airliners through the demodulation of Automatic Dependence Surveillance-Broadcast system (ADS-B) signals is presented. This antenna is designed for being embedded on the top of a drone in order to detect and avoid collisions with airliners. This antenna consists of an array of Planar Inverted-F Antennas, a quadrature feed network (FN) and a reflector plane (RP). The FN is designed to have output signals with the same amplitude and a 90° phase difference between each other. It achieves circular polarization and maintains the axial ratio of the antenna under −3 dB at the desired frequency (1.09 GHz). The antenna with the FN was manufactured and characterized. It weighs approximately 145 kg with its RP. The measured gain of the proposed antenna is about +3.7 dBi. To validate the design, the manufactured antenna was tested with a Universal Software Radio Peripheral for the processing of ADS-B signals at the French National Microwaves Days 2019 (JNM) student contest. The detection of airliners can reach up to 437 km.

中文翻译：

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用于检测客机的微型无人机天线设计

本文介绍了一种专用于通过自动相关监视广播系统 (ADS-B) 信号解调来检测客机的微型天线的设计。该天线设计用于嵌入无人机顶部，以检测并避免与客机发生碰撞。该天线由平面倒 F 天线阵列、正交馈电网络 (FN) 和反射器平面 (RP) 组成。FN 设计为具有相同幅度和 90° 相位差的输出信号。它实现了圆极化，并在所需频率（1.09 GHz）下将天线的轴比保持在 -3 dB 以下。带有 FN 的天线已制造并进行了表征。它的 RP 重约 145 公斤。建议天线的测量增益约为+3.7 dBi。为了验证设计，制造的天线在 2019 年法国国家微波日 (JNM) 学生竞赛中使用通用软件无线电外设进行了测试，以处理 ADS-B 信号。对客机的探测可达437公里。