Land surveying is a process that involves gathering a bunch of information about the positions of certain points and determining the angles between them. What better way to do that than with the help of proper GNSS survey equipment? GNSS accessories have helped to revolutionize the way professionals conduct their surveys as they not only make things a lot easier, it helps with the accuracy and overall quality of work.
Properly conducting GPS/GNSS surveying involves the use of a couple of tools. We want to emphasize and help you understand which are the tools taht you are going to be bringing along with you to help you get the best possible survey results.
What Is GPS and How Is It Used in Land Surveying?
GPS is an abbreviation that stands for Global Positioning System and it is just one of the available GNSS systems that surveyors can use during their work. It uses signals made available from satellites to help pinpoint the exact locations on Earth. GNSS systems can also provide you with additional information like velocity and time synchronization, which can be essential during some types of surveys.
Generally speaking, the main uses of GPS involve:
- Location - Determining a position
- Navigation - Moving from one place to another
- Timing - Making precise time measurements
- Mapping - Creating a map of an area
- Tracking - Monitoring the movement of a person or object
Surveying became one of the first commercial uses of GNSS technologies. As it can help to provide accurate latitude longitudinal location information even in various bad weather conditions, a survey GNSS is made possible no matter the location and the situation in the field.
What Are the Necessary GNSS Survey Equipment to Use?
Different types of GNSS GPS survey equipment are used depending on the situation and type of survey. The three most basic methods that surveyors use to obtain information involve Static GPS Baseline, Real-Time Kinematic (RTK) Observations, and Continuously Operating Reference Stations (CORS). However, no matter the method you decide to use or the approach you choose, there are still some standard pieces of equipment that you are going to have to bring with you.
GPS Receivers
GPS/GNSS receivers represent perhaps the most important piece of equipment for surveyors as they help to catch satellite signals. There are multiple types of receivers available. While all of them mostly do the same, the differences lie in their performance and the additional features that they have. These features and the receiver’s performance certainly make a difference, depending on the type of job you plan to do, so you should base them on your requirements for the survey.
Product Name | Satellite Systems Supported | RTK Accuracy | Tilt Survey Accuracy |
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South Insight V2 GNSS Receiver | GPS, GLONASS, BeiDou, Galileo, QZSS, and SBAS | Horizontal: 8mm + 1ppm; Vertical: 15mm + 1ppm | <10mm + 0.7mm/° tilt, up to 60° |
South INNO8 GNSS Receiver | GPS, GLONASS, BeiDou, Galileo, QZSS, and SBAS | Horizontal: 8mm + 1ppm; Vertical: 15mm + 1ppm | <10mm + 0.7mm/° tilt, up to 60° |
South G4 GNSS Receiver | 1698 channels for robust multi-constellation tracking (GPS, GLONASS, BeiDou, Galileo, SBAS, QZSS, and NavIC) | Horizontal: 8mm + 1ppm; Vertical: 15mm + 1ppm | Up to 60° tilt, <10mm + 0.7mm/° accuracy |
Alpha 4i RTK - GNSS Receiver | GPS, GLONASS, Galileo, BDS, QZSS, SBAS, NAVIC | H: ±(8+1×10⁻⁶×D) mm, V: ±(15+1×10⁻⁶×D) mm | 0-90°, Update Rate 100Hz |
South INNO7 GNSS Receiver | 1598 GNSS channels for multi-constellation tracking | Horizontal: 8mm + 1ppm; Vertical: 15mm + 1ppm | <10mm + 0.7mm/° tilt, up to 60° |
South G7 GNSS Receiver | 1598 channels with multi-constellation tracking (GPS, GLONASS, Galileo, BeiDou, QZSS) | Horizontal: 8mm + 1ppm; Vertical: 15mm + 1ppm | <10mm + 0.7mm/° tilt, up to 60° |
South ALPS1 GNSS Receiver | 1698 channels for GPS, GLONASS, BeiDou, Galileo, QZSS, and SBAS tracking | 8mm + 0.7mm/° tilt accuracy, up to 60° tilt | Up to 60° tilt |
South Insight V3 GNSS Receiver | GPS, GLONASS, BeiDou, Galileo, QZSS, SBAS, and IRNSS | Horizontal: 8mm + 1ppm; Vertical: 15mm + 1ppm | <8mm + 0.7mm/° tilt, up to 60° |
Data Collector
Data collectors are portable devices whose role is self-explanatory. They are used to collect, store, and process the acquired GPS data. It basically acts as an interface between the GPS receiver and the user. Data collectors with a user-friendly interface and more storage are the ones you should be looking for.
You should also know that there are data collectors that have their own built-in GPS, meaning that you don’t need a separate GPS receiver to use them. Additional important aspects when picking data collectors are considering their battery life, durability, and software compatibility.
Surveying Pole
Survey poles are used to elevate GPS antennas to help the GPS receiver stick out above other objects so there is no interference with the coming satellite signals. Most modern survey poles come with an IMU tilt sensor, but what they primarily need to have is a bubble level which helps to determine accuracy while measuring.
Be sure to get the pole with a mounting bracket as well, needed to attach the antenna, and a carrying case, which will make carrying the equipment around the survey site a lot easier.
GNSS Poles |
Specifications |
GPS Pole with Twist Lock and 30' Circular Vial - 2.20/2.50m Carbon Fiber |
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Controller Bracket
To help free up your hands and make it so you don’t have to hold your data collector all the time while doing work, you can mount it to a controller bracket. This piece of GNSS surveying equipment is often overlooked but can very much help speed up the entire surveying process. Make sure to fit the controller bracket that fits the controller you plan to use, especially if you are using a tablet as your controller.
Software
GPS software essentially helps to analyze the collected GPS data. The most important part that you need to have in mind is that the software you decide to use is compatible with the GPS receiver and the data collector. There are certain software types that have integrated features like mapping, contouring, and geocoding, which are certainly going to come in handy during some surveys.
Tripod
If you are using a rover or a base set, you are definitely going to need a tripod. Positioning a GPS receiver on a fixed location helps to ensure accuracy, and that is exactly what a tripod is for. Tripods provide a steady surface for both the receiver and the antenna. You should get one that is adjustable, so you can set it at the required height, and a durable one, so it can withstand the harsh environments that you may happen to work in. But, be sure to pick a lightweight one, made out of fiberglass or wood.
Survey Tripod |
Specifications |
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Radio Modem
Radion modems are also only used when working with a base set or a rover. With the help of a radio modem, your base receiver can transmit the GPS data to your rover’s receiver and that way ensure pinpoint accuracy. However, most GNSS receivers already have a built-in radio modem, so you are only going to need this part if your setup requires it.
The Pros and Cons of GPS for Land Surveying
While GNSS systems have changed the way surveyors do their work, it is not without its shortcomings. While most agree that it generally comes with various positive aspects, there are a few shortcomings that cannot be overlooked, especially if you want to get the best possible results during a survey.
Pros:
- Offers much higher accuracy than conventional survey methods.
- Calculations are made much faster.
- There are no constraints such as visibility problems between stations.
- GPS components can be moved around with ease.
- Certain GNSS systems have the ability to communicate wirelessly.
Cons:
- GPS equipment requires a clear view of the sky to receive signals.
- There is a possibility of signal interference due to surrounding structures or foliage.
- There is a risk of battery failure during long surveys.
- Special types of equipment can be a bit costly.
FAQs
For additional info about GNSS survey equipment, here are some additional answers.
What is GNSS in surveying?
GNSS surveying utilizes satellite signals to provide precise geographic location data, significantly enhancing the accuracy and efficiency of surveying tasks compared to traditional methods. This technology allows surveyors to complete complex measurements quickly, often achieving centimeter-level precision in real-time, which is crucial for applications in construction, agriculture, and urban planning.
What is GNSS equipment?
GNSS equipment encompasses a variety of tools, including GNSS receivers, antennas, data collectors, and RTK systems, that utilize satellite signals to achieve precise positioning for surveying tasks. This technology is essential for modern applications in construction, agriculture, and environmental monitoring, enabling accurate and efficient data collection.
How to use GNSS receiver?
To use a GNSS receiver, set it up in a stable location, configure the necessary settings for either base or rover mode, and initiate data collection while ensuring a fixed position solution is achieved. After collecting the data, save it to the receiver's memory or transfer it to a computer for further analysis.