How Does RTK System Work in Adverse Weather Conditions?

RTK maintains accuracy of 8-15 millimetres even when it's pouring rain or you can't see anything through fog. The reason is simple: satellite signals operate on frequencies that pass freely through clouds, water and snow. Atmospheric attenuation from all these obstacles amounts to only 2 decibels. The base station transmits corrections in real time, whilst the receiver eliminates ionospheric and tropospheric delays automatically. Therefore weather has almost no impact on the result.

Why Rain Doesn't Interfere with the Signal

GNSS operates on L1 (1575 MHz) and L2 (1227 MHz) frequencies. These radio waves belong to the decimetre range. Raindrops, snowflakes and fog are transparent to them. The frequencies were specifically chosen to work in any weather.

Surveyors with 25 years of experience say that rain has never once spoilt their measurements. Even downpours create such weak attenuation that it gets lost against the background of natural signal fluctuations. The system simply doesn't notice the difference between clear weather and rain.

Snow isn't a problem either, as long as it doesn't accumulate in a thick layer on the antenna itself. But that's already a mechanical obstacle, not atmospheric influence. The signal passes through falling snow without difficulty.

How Atmospheric Effects Compensation Works

RTK uses a base station within a radius of up to 20 kilometres. The station transmits data about the carrier wave phase. The mobile receiver compares this data with its own measurements. Since both devices see satellites through the same atmosphere, most errors cancel each other out.

The ionosphere delays the signal due to charged particles in the upper layers of air. The troposphere influences through temperature and humidity near the earth's surface. But when the base and receiver are located close to each other, they experience identical delays. The differential calculation method excludes these errors from the final result.

Multi-frequency receivers catch signals from 25 satellites or more. If one signal weakens, the system uses others. Such reliability reserve works better than any filters.

Real Accuracy Figures

Typical RTK accuracy is 8 millimetres plus 1 part per million horizontally. Vertically it's 15 millimetres plus 1 part per million. At a distance of 10 kilometres from the base, horizontal accuracy will be 8 mm plus 10 mm, that is 18 millimetres in total.

Atmospheric precipitation doesn't change these figures. Neither rain, nor fog, nor clouds. The difference between clear and overcast weather lies within the instrument's natural error margin. Measurements show the same thing accurate to within several millimetres.

For comparison: ordinary GPS in a phone has an error of 1-3 metres. Differential correction systems without RTK provide accuracy from 15 centimetres. RTK works two orders of magnitude better than these technologies.

Operation at Night and Zero Visibility

RTK doesn't need lighting. The system relies exclusively on radio signals from satellites. Therefore it works equally well during day and night, in clear weather and thick fog.

For agriculture this provides an opportunity to increase productivity by 30-40%. A tractor with autopilot moves across the field with 3 centimetre accuracy even when the driver can't see anything ahead. Automatic section control systems don't depend on visibility.

You can sow, spray, harvest at any time of day. This allows completing work within optimal agronomic timings, without waiting for good weather or morning dew.

What Actually Creates Problems

Thunderstorms are dangerous for electronics. Static voltage during a thunderstorm can damage radio modems even without a direct lightning strike. There are documented cases of such damage. Therefore it's better to stop work during storm activity.

Thick ice on the antenna impairs reception. Ice build-up exceeding 30 centimetres of snow can reduce the number of visible satellites. Professional antennas often come with domes or heating systems for winter operation.

Low temperatures affect batteries, not the signal. Receivers operate from minus 40 to plus 65 degrees. But batteries in frost deliver less energy, so they need more frequent charging or larger capacities.

Physical Obstacles Matter More Than Weather

Trees with wet foliage significantly weaken the signal. Water in plant tissues absorbs microwaves. Placing an antenna under a canopy can reduce accuracy to 10-20 centimetres or completely disrupt solution fixing.

Tall buildings and metal structures reflect the signal. The reflected signal travels a longer path and mixes with the direct one. This distorts measurements. In surveying this phenomenon is called multipath propagation.

Mountainous terrain limits satellite visibility above the horizon. In a narrow valley between high mountains only half the sky may be visible. This reduces positioning accuracy and reliability.

Communication quality between base and receiver is critically important. Either UHF radio or mobile internet is used. Modern systems have two SIM cards from different operators. When connection is lost, automatic switching takes 2 seconds.

Base Station Networks

National networks of continuously operating stations cover entire countries. The user connects via internet to the nearest station or receives data from a virtual base. The virtual base is created programmatically taking into account the receiver's position based on several physical stations.

Such technology provides 1-2 centimetre accuracy across the entire coverage area. There's no need to install your own base station and wait an hour for initialisation. Connect to the network and immediately get millimetre accuracy.

When RTK is lost, some receivers automatically switch to satellite correction like SBAS. Accuracy drops to 10 centimetres, but work continues. There are systems with PPK mode support, when data is processed after work completion. This is useful for drones in remote areas.

Equipment Protection

Professional RTK receivers have IP67 or IP68 protection. This is complete dust impermeability and the ability to submerge in water to a depth of up to a metre. Even with the battery compartment cover removed, water doesn't get inside the housing.

Older models didn't always have proper protection. Surveyors would pull on plastic bags or place upturned buckets on top. Now that's not needed. Modern instruments work in rain without additional protection.

Base stations are equipped with uninterruptible power supplies. They operate even during power outages. Backup communication channels guarantee correction transmission in any situations.

Practical Benefits in Farming

The ability to work regardless of weather and time of day reduces equipment downtime. Field operations are performed within optimal agronomic timings. Precise positioning eliminates overlaps during sowing and treatment. This saves seeds, fertilisers and fuel.

Drones with RTK modules provide photo georeferencing accuracy up to 4 centimetres. There's no need to place ground control points across the entire field. This speeds up mapping and reduces labour costs.

Surveyors achieve 2-3 centimetre accuracy during topographic surveys. No need to stand at each point for 20-30 minutes for static observation. Approach, fix coordinates in 5 seconds, move on.

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Summary: Rain, fog, clouds and other atmospheric phenomena don't affect RTK operation. Satellite signals pass freely through precipitation. Differential processing eliminates atmospheric delays. The system provides 8-15 millimetre accuracy regardless of weather. This makes RTK a reliable tool for round-the-clock operation throughout the year.