Abstract

The South African Network of Continuously Operating GPS Base Stations

Richard Wonnacott
Director of Survey Services, Chief Directorate: Surveys and Mapping, South Africa

One of the responsibilities of the Chief Directorate: Surveys and Mapping (CDSM) is the establishment and maintenance of a national control survey network. The network of trigonometrical beacons and town survey marks is known as a passive network which consists of nearly 29000 trigonometrical beacons alone. The introduction of space based global navigation satellite systems, such as GPS, opened up the potential for CDSM to provide an active control survey network in the form of a network of continuously operating GPS base stations. CDSM has adopted GPS technology to establish such a network of base stations known as TrigNet and which currently consists of 45 stations distributed throughout South Africa. The paper describes the basic architecture, the post processing and real time services and the methods of delivery of such services, the current status, applications and future developments of TrigNet.