Systems and methods for ADS-B validation using vehicles

A method of validating Automatic Dependent Surveillance-Broadcast (ADS-B), comprising:

• receiving, from multiple vehicles that are time synchronized, ADS-B data with a timestamp, wherein the ADS-B data includes an identifier of a first vehicle that sent an ADS-B message, horizontal position information in the ADS-B message, and altitude information in the ADS-B message, wherein the timestamp defines a time of reception of the ADS-B message from the first vehicle by each respective vehicle of the multiple vehicles;
• receiving, from each of the multiple vehicles, a determined position of the respective vehicle at the time of reception of the ADS-B message from the first vehicle;
• determining differences in time of arrival for the ADS-B message from the first vehicle to each of the multiple vehicles;
• extracting the altitude information from the ADS-B data;
• determining an estimated horizontal position of the first vehicle based on the differences in time of arrival, the determined positions received from each of the multiple vehicles, and the extracted altitude information;
• and
• determining whether the horizontal position information in the ADS-B message from the first vehicle is valid based on a comparison of the estimated horizontal position of the first vehicle and the horizontal position information in the ADS-B message from the first vehicle.

A ground station, comprising:

• one or more receivers configured to receive respective timestamped ADS-B data and respective position information from multiple vehicles, wherein the respective timestamped ADS-B data from each respective vehicle includes a respective timestamp indicating a time when the respective vehicle received an ADS-B message from a first vehicle, wherein the respective position information from each respective vehicle includes a position of the respective vehicle at the time when the respective vehicle received the ADS-B message from the first vehicle;
• and
• one or more processors communicatively coupled to the one or more receivers and a memory, wherein the one or more processors are configured to:
• determine differences in the respective timestamps for the respective timestamped ADS-B data from the multiple vehicles;
• extract altitude information from the timestamped ADS-B data;
• determine an estimated horizontal position of the first vehicle based on the differences in the respective timestamps for the respective timestamped ADS-B data from the multiple vehicles, the respective positions for the multiple vehicles, and the extracted altitude information;
• and
• determine whether horizontal position information in the timestamped ADS-B data is valid based on a comparison of the estimated horizontal position of the first vehicle and the horizontal position information in the timestamped ADS-B data.