The Technical Logic Behind Drone Navigation and "Satellite Spoofing"
In the common understanding, measuring distance involves measuring with a ruler or radar, a direct perception of "space." However, in modern radio positioning technology, a more fundamental truth is this: we never directly measure distance; we infer distance by measuring time.
The core of this principle lies in a universal constant: the speed of light. The speed of light (approximately 300,000 kilometers per second) is the ultimate speed limit for information transmission. Both the signals emitted by GPS satellites and the radio waves received by drones travel at this speed. Therefore, when we say "measuring the distance between a drone and a satellite," what we're actually doing is extremely precisely measuring the time it takes for the radio signal to travel from the satellite to the drone. Multiplying this time by the speed of light yields the geometric distance between them.
Distance = speed of light × time—this simple formula is the cornerstone of the entire global satellite navigation system.
From "One Dimension" to "Three Dimensions": Three-Sphere Intersection Positioning
Now that we know how to measure distance, the next step is how to locate the target. Currently, mainstream global navigation satellite systems (GNSS), such as the US GPS, Russia's GLONASS, Europe's Galileo, and China's BeiDou, all rely on a classic geometric principle: three-sphere positioning.
We can understand it this way:
First Sphere: The drone measures the precise distance to the first satellite, for example, 20,000 kilometers. With this satellite as the center and a radius of 20,000 kilometers, a large sphere is drawn in space. The drone must be located at a certain point on this sphere. But this isn't enough, as there are too many points on a sphere.
Second Sphere: The drone measures the distance to the second satellite, for example, 21,000 kilometers. Similarly, a second sphere is drawn with the second satellite as the center. The intersection of these two spheres forms a ring. The drone's position is narrowed down to this ring.
The Third Sphere: Finally, the drone measures the distance to the third satellite. This third sphere intersects the aforementioned circle at two points. One of these points is usually in an absurd location outside Earth (such as outer space) and can be easily eliminated. The single remaining intersection is the drone's three-dimensional coordinates (longitude, latitude, and altitude).
This is why positioning requires at least three satellites. In practical applications, a fourth satellite is often needed to provide calibration parameters to correct for minor errors in the receiver's clock (which can significantly affect time measurement accuracy).
Navigation Signal "Attack and Defense": Simulated Satellite Spoofing Technology
With this understanding, we can delve into a critical and sensitive technical area: navigation spoofing. Since drone positioning relies entirely on receiving and trusting satellite signals, what if we could simulate stronger satellite signals on the ground?
Our simulated satellite signal processing module is based on this logic. Its workflow can be summarized as follows:
Real-time Monitoring:
The module continuously monitors the actual satellite navigation signal power that the drone can receive at its current location.
Power Suppression:
When the module is activated, it generates a simulated satellite navigation signal. The key to this "fake signal" is that its transmission power is precisely cut in at a level at least 1dBm higher than the real signal. In the radio world, receivers (drones) naturally tend to lock onto and decode stronger signals.
Continuous Control:
Once the drone "acquires" our simulated signal, the module stabilizes the signal power at a level at least 3dBm higher than the real signal, ensuring that the drone continues to trust the navigation information we provide, completely freeing it from the control of the real satellite signal.
Coordinate Injection:
At this point, we can use this simulated signal to continuously send our preset, false longitude and latitude coordinates to the drone. The drone will use these false coordinates for positioning and navigation, ultimately being "tricked" into a desired path or location without realizing it.
This technology has important applications in low-altitude security, such as protecting sensitive areas, countering unauthorized drone intrusions, and directional guidance. It provides a non-destructive, high-precision active control method.
If your work involves low-altitude economics and airspace safety management, and you are interested in cutting-edge navigation deception technology solutions, please feel free to contact us. We look forward to in-depth discussions with our "low-altitude friends" and jointly exploring a safer and smarter future for low-altitude applications.
