Tech Chat | A Comprehensive Introduction & Guide to CORS

With the widespread application of high-precision GNSS, CORS networks stand as pillars, offering indispensable differential data for accurate positioning across diverse industries. CORS network construction by governments and individuals worldwide is progressing rapidly. 

In previous blogs, we have successively introduced the definition of CORS, some steps for building a CORS website, different configuration methods of a CORS website, etc. In this blog, we will combine and summarize previous blogs and comprehensively introduce the definition, advantages, applications, construction and configuration of CORS to give you a complete understanding. 

1. What is CORS?

A CORS (Continuously Operating Reference Station) network is a network of GNSS reference stations that transmit GNSS raw data and RTK correction data to the data processing center, then it can provide various types of real time correction data to users within the CORS network coverage and for different applications that need GNSS positioning and navigation information

Refer to our previous blog for an in-depth explanation of CORS and its composition: Tech Chat | How does CORS work?

What is VRS?

VRS (Virtual Reference Station) is a network RTK technology. Normally Nearest and VRS are the most commonly used methods.

• NEAREST: Automatically select the differential data sent by the base station closest to the Rover according to the location of the Rover.
• VRS: Generate a virtual base station beside the rover within several meters by modeling real time GNSS errors based on at least 3 base stations of the area, which can largely shorten the baseline and improve RTK accuracy.

Refer to previous blog for details: Tech Chat | What is VRS and its advantages? 

2. Advantages of CORS

For Users:

• Convenience: No need for the setup and configuration of base
• Cost Effective: Avoid the expense of purchasing base
• Standard: All base stations are in the same reference coordinate system, no need for repetitive calibration.
• Accurate: Largely reduce RTK errors caused by baseline distance via VRS

For CORS Providers:

• Expanded User Base: Except traditional surveyors and GIS users, there will be more usersfrom a broader range of applications requiring high precision GNSS PNT information.
• Increased Profitability: In addition to the profit directly from selling CORS account, with trust from increasing CORS users, it is easier for GNSS RTK equipment selling.

3. Applications of CORS

Type 1: Single Station or Small Scale CORS - Private Use

• Deployed at a fixed construction project site, facilitating construction machinery operations and on-site surveying.
• Installed on a designated farm, optimizing smart farming systems within the agricultural environment.
• ......

Type 2: Large Scale or National Scale CORS – Facing Public Users

• Established by GNSS RTK equipment sellers to enhance distribution and service accessibility for their user base.
• Implemented by government or official organizations to support national infrastructure construction projects.
• ......

4. How to build a CORS station?

To build a CORS station, there are 4 main steps.

Step 1: Site Selection

Station Distribution: Tech Chat | How To Site A CORS Station?
Station GNSS data quality analysis: Tech Chat | How to build a CORS station? – Chapter 1

Step 2: Installation

Follow installation guidelines for optimal performance: Tech Chat | How to build a CORS station? – Chapter 2    

Step 3: Configuration

(1) Select a suitable server and establish a stable network environment for continuously run the CORS software/platform.

Refer to the following blogs to select a suitable server:

- How to select a server? Tech Chat | How To Choose An Ideal Cloud Server For Your CORS Software?

- Example of Amazon Cloud:
Tech Chat | How to build your CORS platform for free? – Chapter 1
Tech Chat | How to build your CORS platform for free? – Chapter 2

- Example of Alibaba Cloud:
Tech Chat | How to build your CORS server for free with Alibaba Cloud?

(2) To continuously upload the CORS station data to the server and remote control the station, you need to configure a stable network environment for each station and be able to visit via public network.

- About static IP, DDNS and NAT-DDNS
Tech Chat | What is DDNS & how does it benefit CORS management?
Tech Chat | What is NAT-DDNS?

(3) After the server and network are set up, you can install the CORS software and configure to upload the CORS station data to the CORS platform. SingularXYZ provides SingularCaster CORS software, and our GNSS receivers are also compatible with mainstream CORS management software on the market.

- Example of SNIP Ntrip Caster configuration: Tech Chat | How to build your CORS platform for free? – Chapter 2
- More about SingularCaster software: https://www.singularxyz.com/SingularCaster.html

5. SingularXYZ CORS Solutions

SingularXYZ provide from hardware, software to technical support one-stop CORS solution for your CORS construction.

Read blog to learn the difference between choosing a geodetic antenna and a choke ring antenna.
Tech Chat | Should I Choose A Choke Ring Antenna For My Reference Station?

Learn more about SV100 CORS solution.
https://www.singularxyz.com/SV100_CORS.html