GPS stands for Global Positioning System , based on Satellite navigation technology. The fundamental techniques of GPS is to measure the ranges between the receiver on land, at sea, in air /space and a few simultaneously observed satellites in space. It was developed by the US DOD under its NAVSTAR satellite program to accurately determine user’s position, velocity and time in a common reference system anywhere and or near the earth on a continuous basis. Through the developments of a few decades, GPS is widely welcomed in many areas, such as navigation, low earth orbit satellite determination, static and kinematic positioning, surveying etc. GPS becomes a necessity for daily life, industry , research and Education. The most important applications are positioning and navigation. It is all weather , space-based navigation system. It includes three major parts: The space segment consisting of satellites, which broadcast signals; The Control segment steering the whole system, the user segment including the many types of receivers.

1 Conventional Static Positioning

It has two or more receiver at two or more stations, simultaneously receive signals from a minimum of four satellites. Baseline accuracy 5mm+1PPM when base line less than 25 KM using single frequency receiver. Relative long time occupation are needed. Bigger than 15 minutes, 30minutes for dual frequency receivers and single frequency receivers. Improve accuracy by increasing the observation time and not use satellite at low elevation angles(e.g. ) 15 degrees)

2 Rapid Static Positioning

Rapid Static Positioning is an extension of the above conventional static positioning to achieve cm-level accuracies in minutes. It includes one or more receivers at the reference stations but remain fixed during the observation period. One or more receivers that occupy rover stations.

Baseline accuracy 5mm+1PPM when base line is less than 25 KM(less than 10KM for L1 only). Relative short time occupation are needed. 3-5 minutes up to 20 minutes at rover station. Do not use satellite at low elevation angles(e.g. ) 15 degrees.

3 Kinematic Positioning

Kinematic Positioning is a productive and accurate method to establish relative survey control. It includes one or more receivers at the reference stations but remain fixed during the observation period. One or more receivers are rovers and move together with moving objects without signal interruption during observation(stay minutes at the start point).

Accuracy is 1-2 cm, 1ppm. Short distance is less than 30 km, data rate is at 1-200 Hz.

4 Stop and Go Positioning

Stop and Go Positioning is a quick method for detail surveying, engineering surveying. .It includes one or more receivers at the reference stations but remain fixed during the observation period. One mobile receiver that first occupies that first point for several minutes in order to get a better positioning initialization, then moves from one to the other point for several epochs up to minutes occupation without signal interruption. Its accuracy is 1-2 cm, 1ppm. Short distance applies.

5 Reoccupation

It includes one or more receivers at the reference stations but remain fixed during the observation period. One or more mobile receiver occupy points of interest for several minutes for a change of satellite configuration without signal interruption. Reoccupy the same points in time.

Accuracy is 5-10mm, 1ppm.Short distance applies.

6 Pseudo-Kinematic Positioning

It is the combination of Stop and Go and Reoccupation method. It observes points for a few minutes(turn off during travel between points). Re-observe the same points under a different satellite geometry, use combined observations to resolve positions and ambiguities.

S980A GNSS Receiver

GNSS Receiver with 5 Watt radio and Atlas®

Stonex S980A integrated GNSS receiver tracks all the present constellations and satellite signals GPS, GLONASS, BEIDOU, GALILEO, QZSS and IRNSS.

Through the 4G GSM modem a fast internet connection is guaranteed and the Bluetooth and Wi-Fi modules allow always reliable data flow to the controller. These features combined with the integrated 2-5 watt radio make S980A the perfect base station receiver.

The color touch display and the possibility of connecting an external antenna makes S980A an extremely effective receiver for every type of job. S980A is also equipped with an E-Bubble and the optional IMU technology: fast initialization, up to 60° inclination.

S980A has a 1PPS port which can be used in applications that require precise synchronization time to ensure that multiple instruments work together or that use the same parameters for system integration based on precise time.

What are the performances of the S980A with IMU?

• Fast initialization
• Up to 60° inclination
• 2 cm accuracy 30°
• 5 cm accuracy 60°
• Fast and precise survey
• No problem of electromagnetic disturbances

Stonex S980A with IMU system makes reliable every measurement, both survey and the stake out jobs, and makes extremely faster the acquisition of points: up to 40% of the field work time can be saved!

S900A New GNSS Receiver

Stonex S900A has two versions, Italy made model is with 3 year warranty, the other has two year warranty. S900A equipped with an high performance GNSS board 800 channels and capable of supporting multiple satellite constellations: GPS, GLONASS, BEIDOU, GALILEO, QZSS and IRNSS, including L-Band correction.

Through the 4G GSM modem a fast internet connection is guaranteed for the reception of correction data and the management of the maps in the background.

In the amazingly compact structure the Bluetooth and Wi-Fi modules allow always reliable data flow to the controller, and the integrated TX/RX UHF radio with selectable frequencies, make S900A the perfect system for a GNSS Base + Rover.

Stonex S900A integrates E-Bubble sensor that allows the measurement of difficult points with the pole not levelled. It is possible to measure points with an inclination of the pole up to 30° even in harsh environments and in the presence of magnetic fields.

S900A is also equipped with the optional IMU technology. Fast initialization, up to 60° inclination.

What are the performances of the S900A with IMU?
• Fast initialization
• Up to 60° inclination
• 2 cm accuracy 30°
• 5 cm accuracy 60°
• Fast and precise survey
• No problem of electromagnetic disturbances

S700A GNSS Receiver

Modular GNSS system

Stonex S700A is a compact, high-performance GNSS receiver features a multi constellation 700 channels GNSS board.

Customer have the ability to purchase an entry level version, only L1 GNSS and, at any time, it is possible to upgrade the receiver to the full version via activation code.

S700A supports GPS, GLONASS, BEIDOU, GALILEO, QZSS and IRNSS. S700A full version supports also L-Band correction.
The unique internal antenna combines GNSS, Bluetooth and Wi-Fi integrated modules to optimize space and increase performance.

Designed for all day use in surveying application, S700A includes several features: Linux Operating System, WEB UI interface, 4G Modem, high battery capacity, Type-C connector and IP67 certification.

Stonex S700A GNSS receiver with full version is an ideal solution for any surveying field work and in particular difficult areas. Atlas® delivers world wide centimetre level correction data through L-band communication satellites.

SC600 GNSS Receiver

STONEX technology for GNSS reference stations and networks continues to evolve, meeting rapidly changing GNSS technology demands.

SC600 GNSS Receiver is a multipurpose receiver that adapts to various types of use.

SC600 is available in two versions:

• Standard version – it includes GNSS, GSM, Radio and 5Hz and it is recommended for monitoring applications, reference stations, RTK base stations.

• Full version – it includes GNSS, GSM, Radio, 20Hz and Heading operation and it is recommended as RTK rover for ground vehicle, marine or aircraft based systems, providing GNSS multiconstellations heading and position data in static and dynamic environments.