GPS (Global Positioning System) Surveying is the most advanced positioning and data recording technology available to the Land Surveyor today. Using available Satellites (Minimum 4), the Receivers record satellite signals and internal receiver software, sub-centimeter accurate horizontal and vertical positioning data is provided about any point or feature. This data can be related either to the National Grid Co-ordinate system or to your project’s own Local Grid. 
The recorded data can be processed and manipulated by various software applications, depending on client requirements. The processed data is then available to the Project Team in various forms to ensure everyone has the highest quality information to hand. The satellites send signals to earth; GPS receivers on the ground pick up these signals. The receivers use the signals from a number of satellites to calculate their own position on the earth's grid reference system with accuracy ranging from 15mm
To 35mm depending on the equipment used.
The equipment we use is mainly the Trimble R10 GNSS GPS and Leica VIVA GS 15 GNSS GPS Smart System with back-up if necessary using Trimble R8 GNSS Model 3, dual frequency, RTK (Real Time Kinematic) system. These are versatile systems, which are capable of bringing control points accurately to the site.