The vulnerability of Positioning, Navigation, and Timing (PNT) services derived from Global Navigation Satellite Systems (GNSS) makes having a resilient and accurate Alternative PNT (APNT) based on high-power terrestrial radio sources necessary. The L-band is very crowded spectral real estate with GNSS, Distance Measuring Equipment (DME) and Air Traffic Control Beacon System (ATCRBS) signals occupying the band from 900–1600 MHz. Thus, as getting new signal and spectrum for APNT would be difficult, we must leverage existing transmissions and infrastructure. The ∼660 Automatic Dependent Surveillance-Broadcast (ADS-B) ground stations in the United States represent significant infrastructure that can be leveraged for APNT. However, as ADS-B was designed for surveillance, it does not inherently possess features necessary to support APNT goals. This paper describes and demonstrates techniques for using ADS-B Universal Access Transceiver (UAT) signals for PNT. We develop methods to use all ground UAT signals to provide robust, multi-frequency pseudoranges. We examine the ranging and positioning performance of the UAT signal on the ground and in flight, to demonstrate its ranging accuracy, and hence the timing and synchronization of the station. We demonstrate and analyze navigation using UAT signals, as well as the intra-system interference challenges of using multiple UAT stations.

中文翻译：

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用于替代定位、导航和授时 (APNT) 的自动相关监视广播 (ADS-B) 通用接入收发器 (UAT) 传输：概念与实践

源自全球导航卫星系统 (GNSS) 的定位、导航和授时 (PNT) 服务的脆弱性使得必须拥有基于高功率地面无线电源的弹性和准确的替代 PNT (APNT)。L 波段是非常拥挤的频谱空间，GNSS、测距设备 (DME) 和空中交通管制信标系统 (ATCRBS) 信号占用了 900–1600 MHz 的频段。因此，由于为 APNT 获取新的信号和频谱很困难，我们必须利用现有的传输和基础设施。美国的 660 个自动相关监视广播 (ADS-B) 地面站代表了可用于 APNT 的重要基础设施。然而，由于 ADS-B 是为监视而设计的，它本身并不具备支持 APNT 目标所需的功能。本文描述并演示了将 ADS-B 通用接入收发器 (UAT) 信号用于 PNT 的技术。我们开发了使用所有地面 UAT 信号来提供稳健的多频伪距的方法。我们检查了地面和飞行中 UAT 信号的测距和定位性能，以证明其测距精度，以及站的定时和同步。我们演示和分析使用 UAT 信号的导航，以及使用多个 UAT 站的系统内干扰挑战。以证明其测距精度，从而证明该站的定时和同步。我们演示和分析使用 UAT 信号的导航，以及使用多个 UAT 站的系统内干扰挑战。以证明其测距精度，从而证明该站的定时和同步。我们演示和分析使用 UAT 信号的导航，以及使用多个 UAT 站的系统内干扰挑战。