Drones in Focus: Navigating the Nuances of Satellite Signal Accuracy

In professional applications of various types of drones – whether they’re airborne vehicles, wheeled platforms, or others – the precision of coordinate determination is crucial.

Traditionally, satellite systems are employed for this purpose, such as the American GPS and its counterparts used in the European Union and China.

In this article, we’ll delve into a series of factors that diminish the accuracy of a drone’s position determination, especially when it’s at a significant distance from the operator’s location.

Weak Signal

There can be several reasons for this phenomenon:

• Operating in areas with many tall buildings and structures. These can attenuate the strength of satellite system signals.
• Insufficient antenna power. This is a design flaw in some drones, introduced by manufacturers either to reduce the cost of the device or to minimize its size and weight.
• Inadequate satellite coverage of the working area. This becomes evident, for instance, when a drone designed exclusively for the Chinese Baidu system is launched in a different region. The visible satellites from this system aren’t sufficient for precise positioning, leading to reduced coordinate determination accuracy.

The latter two shortcomings can be rectified. It’s merely a matter of selecting a drone equipped with a high-quality professional antenna and a navigation chip that supports at least the two primary standards: GPS and Baidu.

For operations in areas with challenging terrains and structures, professional RTK drones can be invaluable. They can interface with a base station – often referred to as an RTK base station. In such scenarios, centimeter-level accuracy in coordinate determination can be achieved. This precision is crucial for search-and-rescue operations, engineering challenges faced during terrain planning, and architectural designs.

Unlike drones, the base remains stationary and is equipped with professional navigation equipment. Its installation location can be chosen in a relatively open area.

Interference

This factor is particularly noticeable in areas with dense construction. However, it can also manifest in open areas, especially if there’s a strong source of electromagnetic radiation near the site of cartographic research.

When interference arises, detecting its presence is crucial. The next step is to try and identify the source of the interference. In some cases, it’s possible to eliminate these disturbances. For instance, one might coordinate with relevant agencies to temporarily shut down the equipment causing the interference during drone operation.

Quality of the Satellite Signal Receiver

Beyond the antenna responsible for the physical reception of signals from navigation system satellites, a drone contains an electronic circuit for digital processing of the received data. In cases of insufficient computational performance, software errors, or poor code optimization, the chip might produce inaccurate coordinates.

This factor should be taken into account when choosing a drone model. Preference should be given to professional models, ideally with a long-standing presence in the market. Errors and inadequate code optimization primarily manifest during the product launch phase. They are gradually rectified as firmware updates are released.

For professional surveys, it’s wise to study the anticipated work area for potential sources of interference. It’s also crucial to select appropriate equipment: the drone itself, an RTK base station (if its use is feasible), to minimize errors in coordinate determination.