Understanding RTK Networks in Canada

In Canada, the adoption of RTK networks has been particularly significant due to the country's vast landscape and varied terrain. In this blog, we’ll explain the fundamentals of RTK technology and explore the role of RTK networks, which allow users to access real-time corrections over vast areas without setting up their own base stations. We'll also explain the landscape of RTK networks in Canada, including both public systems like the Canadian Active Control System (CACS) and private networks like MeasurNET, so you can choose the solution that best fits your needs.

RTK is a high-precision GNSS (Global Navigation Satellite System) technique that enhances the accuracy of position data. Traditional GPS devices provide accuracy within a few meters, which may be sufficient for general navigation but inadequate for tasks that require pinpoint accuracy. RTK technology corrects GPS signals in real-time, reducing the margin of error to within centimeters or millimeters.

RTK works by using two main components:

• A base station (fixed) that knows its exact location.

• One or more rovers (mobile receivers) that calculate their position relative to the base station.

The base station collects satellite data and transmits corrections to the rover(s), which can then determine their position with high precision.

An RTK network eliminates the need for users to establish their own base stations. Instead, the RTK network consists of a series of permanently installed base stations that are strategically placed throughout a region. These base stations are connected to a central server that processes the data and provides real-time corrections to users.

For professionals working across large areas, RTK networks provide several advantages:

• Increased flexibility, as users can access the network without setting up their own base stations.

• Continuous coverage, allowing for high-precision measurements over a wide geographical area.

• Cost-effectiveness, since users don’t need to invest in base station equipment and maintenance.

An RTK network is designed to continuously receive GNSS signals from satellites. Here’s a summary of how the data flow works:

1. Satellite Signal Reception: Reference stations receive satellite data, which includes positioning information.

2. Error Detection: These stations calculate errors caused by atmospheric distortion, satellite clock inaccuracies, and signal obstructions.

3. Correction Generation: The data is processed to generate precise correction information, which accounts for location-specific errors.

4. Transmission to Rover: This correction data is broadcasted to connected rovers, which apply it to enhance their positional accuracy in real time.

5. This process happens in milliseconds, allowing operators to receive real-time, centimeter-level accuracy across large regions.

RTK technology has long been hailed for its ability to enhance the accuracy of GNSS data. Traditionally, this involved a setup with a base station providing corrections to a rover over a limited range. The introduction of RTK networks, however, changes this paradigm. RTK networks consist of a series of continuously operating reference stations (CORS), which work together to provide real-time corrections to rovers across much larger areas.

• Scalability: RTK networks cover extensive geographic areas without the need for users to set up and manage individual base stations.

• Data Reliability: Multiple reference stations ensure redundancy, reducing the impact of signal loss or temporary interference.

• Mobility: Operators can move freely within the network’s range without losing precision, ideal for dynamic industries like construction and agriculture.

Canada has a well-established infrastructure for RTK networks, with coverage available in most populated and key industrial areas. Various public and private entities manage these networks, providing access to real-time correction data for a wide range of industries.

The Canadian Active Control System (CACS) is a network of permanently installed GNSS receivers managed by Natural Resources Canada (NRCan), a government body responsible for providing geospatial data and services across the country. CACS is part of a broader infrastructure that helps maintain geodetic reference systems essential for mapping and positioning services in Canada.

• Nationwide Coverage: CACS provides correction data across all regions of Canada, including remote areas.

• Free Access: Since it’s a government-operated service, the data provided by CACS is publicly available. This is especially beneficial for scientific research, educational institutions, and public sector projects.

• Scientific and Environmental Focus: While CACS can be used for a variety of applications, it primarily supports scientific research, land surveying, engineering, and environmental monitoring. It is widely used by government bodies, universities, and research institutions for projects like tectonic studies, sea level monitoring, mapping, and climate change tracking.

• Static and Real-Time Services: CACS provides both static GNSS data for post-processing and real-time corrections for users in need of instant positional accuracy. However, it may not always be as optimized for high-precision, real-time applications compared to private networks that focus on immediate access and high reliability.

MeasurNET and other private RTK networks offer subscription-based access to real-time GNSS corrections, focusing on urban, industrial, and remote regions where precise, centimeter-level positioning is essential. These networks are built to provide on-demand services for professionals who need continuous, reliable data without having to set up their own base stations.

• Subscription-Based Access: Unlike CACS, private RTK networks offer services on a paid subscription basis. Users, ranging from small businesses to large enterprises, can choose from different service tiers based on their requirements.

• Real-Time Focus:Private RTK networks prioritize real-time, high-precision corrections, which are essential for dynamic applications like precision farming, construction, and drone mapping. They are optimized to ensure low latency, providing corrections with minimal delay.

• Advanced Technology and Reliability: Private networks are typically built with robust infrastructure that includes backup systems to ensure consistent uptime and service availability. Providers often integrate redundant base stations and advanced monitoring to maintain uninterrupted service in critical applications.

Despite their advantages, RTK networks are not without challenges. Users in remote areas may experience issues with connectivity, as many RTK networks rely on mobile internet or radio communication to deliver correction data. This makes it important for users to evaluate the availability of infrastructure in their operational regions.

For industries working in off-grid or rural areas, hybrid RTK solutions, which combine base station setups with RTK network access, may be more practical. These hybrid models allow operators to switch seamlessly between a base station and the network depending on the available connectivity.