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A word about Datum: to understand how SBAS systems work (WAAS / EGNOS /MSAS / GAGAN) lets discuss factors affecting local DGPS accuracy.

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Field Study - SXblue receivers: overcoming position error and achieving sub-meter horizontal accuracy with SXblue mapping grade receiver. Discussing data collection software, LIDAR DATA, SBAS, forest canopy percentage and other important factors.

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Atlas® GNSS Global Correction Service
Superior Positioning Accuracy, Positioning Sustainability and Convergence Time.

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Centimetre accuracy using RTK Networks

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SXblue Toolbox: mapping software allowing post-processing activities on computers and mobile phones for surveying and geomatics professionals. Can connect to a NTRIP server for RTK corrections. Provides superior positioning accuracy.

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GPS – The Error Budget Learn about dilution of precision, positioning accuracy, GPS Post Processing and Real-Time Kinematics

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Field Genius
Survey software / data collection tool featuring RPN calculator, Digital Terrain Modelling and other geoinformation tools.

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External references on:
WAAS service, SatNav, EGNOS, MSAS & more.

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GPS stands for global position system, a (US satellite-based). GPS might refer by extension to the receiver. GNSS stands for Global Navigation Satellite System and regroup every regional satellite navigation system (GPS, GLONASS, BEIDOU, GALILEO, ect.).
A Differential Global Positioning System (DGPS) is a broad term that describes various ways of enhancing the Global Positioning System (GPS). It provides improved location accuracy from the nominal GPS accuracy (15 meters) to about 1-3 cm in case of the best implementations. All SxBlue’s receivers are DGPS systems using SBAS corrections.
Satellite-based Augmentation System (SBAS) augments GNSS constellation(s) by providing ranging, integrity and correction information. While the main goal of SBAS is to provide integrity assurance for aviation, it also provides sub-meter (<1m) accuracy free of charge in various regions (see here).
Yes, these services have proven themselves for some time now and have shown excellent results. As WAAS (North and Central America), EGNOS (Europe), MSAS (Japan) and GAGAN (India) are operational, they can be used as sole means of navigation. We recommend that you refer to for Web sites that provide details on the operational status.
Atlas is a GNSS-based global L-band correction service, providing its correction signals via L-band satellites at accuracies ranging from sub-meter (<1m) to sub-decimeter (<10cm) levels depending on subscription. The entire globe (75°N to 75°S) is virtually covered.
RTK stands for Real-Time Kinematic. It uses sophisticated techniques to reduce and remove errors common to a base station (or RTK network) and rover pair. RTK is used for applications that require higher accuracies, such as centimetre-level positioning, up to 1 cm. Most of these network users will need cellular coverage and data plans for RTK on the field.
It is an SBAS system provided by the USA FAA covering North America free of charge.
GNSS are faster and more stable due to their capacity to rely on more satellites. Differences are proband in cities, forests or other areas where line of sight with sky is obstruct.
The positions computed by your receiver are accurate (guaranteed) to within 1 meter 95% of the time (assuming a good view of the sky and minimal multipath). This accuracy is, conservatively, halve for z-values. With RTK corrections, it can go down to centimeter precision. Contact us for more details.
SXBlue receivers are a unique solution in that they are very compact, yet deliver very high performance. There are a number of DGPS products on the marketplace but very few of them are suitable for commercial use with such applications as GIS Mapping, due to their positioning performance and their update rates. SXBlue is up to the task and meets the needs for these applications. SXBlue also offers the facility of outputting raw measurement data for post-processing in the office.
For the best performance, please ensure that the sky above the SXBlue antenna is unobstructed for satellite tracking. The receiver tolerates a certain amount of signal blockage due to the availability of redundant satellites (only four are required for a position). However, the more satellites are blocked, the more impact this could have on your positioning accuracy.
Yes, we designed a model specifically for that purpose. A cigarette lighter plug is available from your dealer as well. It is important to use a proper charger manufactured by SXblue.
A Differential Global Positioning System (DGPS) is a broad term to describe ways of enhancing the Global Positioning System (GPS). It provides improved location accuracy from the 15 meters nominal GPS accuracy to about 1-3 cm in case of the best implementations. All SxBlue’s receivers are DGPS systems using SBAS corrections.
SXBlue supports standard NMEA data messages. The $GPGSV data message contains satellite tracking information. Since the GPS automatically tracks GPS satellites when powered, this will give you information on the tracking status. If your receiver has computed a position, this will be contained within the $GPGGA data message. Additionally, SXBlue receiver has LEDs that give status indications.
Yes, you may have different NMEA messages turned on for the ports. Further, these NMEA messages may also be at different update rates.
GGA - essential fix data which provides 3D location and accuracy data. $GPGGA,123519,4807.038,N,01131.000,E,1,08,0.9,545.4, M,46.9,M,*47
GP means that it is a GPS position (GL would denote GLONASS).
GGA Global Positioning System Fix Data
123519 Fix taken at 12:35:19 UTC
4807.038,N Latitude 48 deg 07.038' N
01131.000,E Longitude 11 deg 31.000'

1 Fix quality:
0 = invalid,
1 = GPS fix (SPS),
2 = DGPS fix,
3 = PPS fix,
4 = Real Time Kinematic,
5 = Float RTK,
6 = estimated (dead reckoning) (2.3 feature),
7 = Manual input mode,
8 = Simulation mode

08 Number of satellites being tracked
0.9 Horizontal dilution of position
545.4,M Altitude, meters, above mean sea level
46.9,M Height of geoid (meaning sea level) above WGS84 ellipsoid
(empty field) time in seconds since last DGPS update
(empty field) DGPS station ID number
*47 the checksum data, always begins with "
Yes, the Serial, USB and Bluetooth ports can be used independently.
Red: when the receiver is powered, this LED will light up.
Green: once the receiver retrieves his position from satellites, this LED will light up.
Orange: as the differential position is computed, this light will stay on.
Yellow: as the receiver connects to SBAS or Atlas, this light will stay on.
Blue: stays on when the receiver and the data collector exchange data.
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Problems are likely to fall within one of the following categories: power, communication, configuration, GPS reception and performance, SBAS reception and performance, external corrections and installation. If the problem persists, please consider contacting your dealer first. Here is a full list of our dealers worldwide. Geneq Technical Support is available during normal business hours (8:30 AM to 5:00 PM Eastern Time, Monday to Friday) at: Tel +1-514-354-2511 / Fax:+1-514-354-6948 /  e-mail:
The Green LED closest to the Red power LED is the GPS indicator. If this is turned off, the receiver is not tracking satellites. If the Green LED is on, the receiver has obtained position.
The second LED closest to the Red power LED is the GPS indicator. If this is turned off, the receiver is not tracking satellites. If the Yellow LED closest to the last blue LED (Bluetooth) is not on, the receiver has not obtained differential LOCK.
If there are any obstructions (trees, buildings, …) move the antenna in clear view of the sky and horizon. You may be experiencing a temporary satellite orbit misalignment. In this case the only thing to do is wait until more satellites are in view of the receiver.
It is most likely a problem with your battery or the power source of your receiver. Please check the following: 1) Make sure your power adapter is still working. 2) Try to plug the receiver directly into your electrical outlet. 3) If there is still no power, please contact us.
The “DIFF” LED is the primary indicator that SBAS signal has been acquired and locked. The iSXBlue/SXBlue allows you to request the output of the $RD1 message that contains the SBAS bit error rate (BER) for both receiver channels. The BER value describes the rate of errors received from SBAS. Ideally, this should be zero; however, the iSXBlue/SXBlue should provide good performance up to a 150 BER. The PocketMAX utility discussed in the PocketMAX Manual is a useful tool that provides this information without needing to use NMEA commands.
1) Examine the SXBlue cables and connectors for signs of damage.
2) Ensure that you have adequate battery charge.
3) Check the documentation of the receiving device if using RS-232, to ensure that the transmit line from the SXBlue is connected to the receiving line of the other device.
4) Ensure that the signal grounds are connected.
5) If using the USB connection, make sure drivers are installed on the computer.
6) If the iSXBlue/SXBlue is connected to a custom or special device, ensure that the serial connection to it does not have any incompatible signal lines present that may not allow either to communicate properly.
7) Try using the Serial port for communication as only pins 2, 3 and 5, which are the only pins required for communication, are connected.
8) Make sure that the baud rate of the SXBlue receiver matches the other device.
9) The other device must also support an 8 data bit, 1 stop bit, and no parity port configuration (8-N-1). Some devices support different settings that may be user-configurable.
10) Ensure that the settings match.
11) Consult the troubleshooting section of the other device's reference manual to determine if there is a problem with that equipment.
Older Bluetooth modules may sometimes have to be replaced due to compatibility issues with newer OS. If you are unable to detect your device, please contact us. If you are able to detect the receiver, your problem is most likely a baud rate issue.
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Geneq introduces battery pack, GPS data collector, Net20 Pro CORS/GNSS reference station receiver

“Initially, a number of DGPS options were tested, and WAAS proved to penetrate our forest canopy type the best. Short outages do occur, but the technology in the SXblue GPS allows our operations to continue virtually uninterrupted.”

J.D. IRWING LTD., New Brunswick, Canada

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Made in Canada since 2003
1 800 463-4363

Your trusted source of geospatial mapping systems

In the demanding world of surveying equipment, SXblue has gained recognition for its state-of the-art technology, developed and manufactured in Canada. Our receivers are DGPS systems using SBAS / WAAS corrections. With RTK GPS corrections, our receivers easily attain centimeter precision. Long-lasting and affordable, our survey tools deliver robust performance even in difficult areas (case study). Also available: SXblue Toolbox, our new iOS app!

GPS - GNSS Receivers
GPS / GNSS receivers: SXblue II series
  • Geospatial mapping with SBAS / WAAS
  • DGPS mapping
  • Multi-GNSS including GPS Glonass Galileo BeiDou QZSS
DGPS Survey / Survey Grade GNSS Receiver
DGPS Survey grade equipment – SXblue Platinum
  • iOS/Android/Windows compatible
  • Compatible with different mapping software such as ESRI
  • All SxBlue’s receivers are DGPS survey systems using SBAS / WAAS corrections.
Vehicle Guidance Receiver
SXblue Platinum AG
  • Precision farming
  • GPS tractor
  • GPS control of vehicles
Reference Station
NET20 Pro
  • NTRIP – unlimited casters/servers/clients
  • Interacts with vast variety of surveying instruments
  • 555 GNSS channels
Receivers with Integrated Antenna
F90 / G10
  • GPS survey equipment
  • Land surveying equipment
  • GNSS RTK smart antenna
Compact GNSS receiver
SXblue Premier
  • 220 / 336 channels
  • 8 GB SSD
  • Magnesium alloy body
  • Lightweight: 500g with battery
  • IP67 – dust and waterproof
Handheld computer
  • All-in-One GNSS receiver
  • Real-Time sub-meter accuracy
  • Field Genius Data collecting software preinstalled
Data Collectors
  • Windows Mobile 6.5 Pro, Android
  • VGA TFT color, Sunlight readable
  • Bluetooth with any SXblue or Smart Antenna
Rugged Tablets
  • Windows 10 or Android
  • IP67, ruggedized tablet
  • 7″, 8″ or 10″ with 4GB RAM/64 GB internal
Professional data collection software
Data Collection Software

field genius

Compatible Applications

fulcrum, terrago, ntrip, cmt, arcpad, esri, amigocollect, fieldscout

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