广域增强系统（Wide Area Augmentation System，简称WAAS）是由美国联邦航空局开发创建的用于空中导航的一个系统，该系统主要是通过解决广域差分GPS的数据通信问题从而提高全球定位系统的精度和可用性。

广域增强系统利用遍布北美和夏威夷的地面参考站（Wide-area Reference Station，简称WRS）采集GPS信号并传送给主控站（Wide-area Master Station，简称WMS）。主控站经过计算得出差分改正（Deviation Correction，简称DC ）并将改正信息经地球站传送给WAAS地球同步卫星。最后由地球同步卫星将信息传送给地球上的用户，这样用户就能够通过得到的改正信息精确计算自己的位置。

The Wide Area Augmentation System (WAAS) is an air navigation aid developed by the Federal Aviation Administration (prime contractor Raytheon Company) to augment the Global Positioning System (GPS), with the goal of improving its accuracy, integrity, and availability. Essentially, WAAS is intended to enable aircraft to rely on GPS for all phases of flight, including precision approaches to any airport within its coverage area.