GPS Spoofing: What It Is and How to Prevent It

This page explains the basics of GPS spoofing and different types. It also details various methods to prevent GPS spoofing of your GPS receiver device on ships, cars, smartphones, drones, etc.

What is GPS Spoofing?

As we know, GPS and GNSS technologies provide RF signals to GPS/GNSS receivers with the help of satellite constellations. These satellites transmit positioning and timing information to receivers on Earth from various directions. GPS/GNSS receivers use these satellite signals to determine their location in terms of latitude and longitude. GPS/GNSS aids in navigation through sea, land, and air, and is used by ships, vehicles, and airplanes. It’s relatively easy to track GPS/GNSS receivers using mobile/web apps.

Other similar technologies include Russian GLONASS, European Galileo, Chinese BeiDou, Japanese QZSS, and the Indian NAVIC system.

Spoofers transmit signals with more power compared to the weak GNSS/GPS signals received by receivers. Moreover, they carry false positioning information to make GPS receivers believe they are at a false location.

There are two main types of GPS spoofing:

• Re-broadcast of GNSS/GPS signals recorded at some other place or time
• Hackers generate and transmit modified satellite signals to the target

Radio interference overpowers weak GNSS signals, causing signal loss and, consequently, positioning loss. During a spoofing attack, a hacker’s radio transmitter located nearby transmits fake GPS signals to the target receiver.

Example #1: If a smartphone is spoofed by a hacker, the smartphone user can be made to believe they are on Mount Everest, even if they are not.

Example #2: A ship can be hijacked by GPS spoofing by diverting its path of travel.

Example #3: Drones can be hijacked and redirected toward their own forces.

How to Prevent GPS Spoofing

Here are several techniques and methods used to prevent GPS spoofing of GPS receivers:

• Spoofing Detection: GPS/GNSS receivers should be able to detect spoofed signals from a mix of authentic and spoofed signals. Once a spoofed signal is detected, it should be excluded from positioning calculations. Interference detection and mitigation devices are available for this purpose.

• Secure Signals: Use signals designed to provide protection from spoofing attacks, such as Galileo OS-NMA and E6 or GPS military code. This way, security is directly incorporated into the GPS/GNSS satellite itself, making signals spoofing-resilient. Galileo is the first satellite to incorporate an anti-spoofing service in the GNSS signal.

• Interference Mitigation: Employ interference mitigation techniques such as Septentrio AIM+ to detect anomalies in the received signal, differentiating authentic GNSS/GPS signals from fake ones.

• Dual-Polarized Antenna: Dual-polarized antenna-based anti-spoofing techniques are under research.

• Disable GPS: The simplest way to protect a smartphone from GPS spoofing is to disable GPS on your phone. To do this, enable “battery saving” location mode, which keeps WiFi and cellular mode ON to determine the location of your device.

  • Go to Settings → Security & Location → Location → Mode → Battery saving.