With increasing development and expansion of Continuously Operating Reference Station (CORS) networks, globally and in Australia, Global Navigation Satellite System users now have the option of utilizing reference station networks to receive correction data and undertake real time surveys without the need of supplying their own base station..The ProMark3 RTK GNSS transmits correction data via a conventional 0.5 watt UHF radio allowing for a working range of up to 1.5km line of sight. Alternatively the ProMark3 can connect to CORS increasing that range up to 10km which is the recommended limit for single frequency RTK.
However CORS coverage is still in its early development and there are large areas in Australia and around the world that have no access to this technology. A user in an area not serviced by CORS would have no
choice but to use conventional radio for communication thus creating the problem of a limited working range.
The main focus of this research project was to develop, test & validate a portable GNSS field solution using Direct IP to overcome working range limitations. Two different reference stations to broadcast
corrections were designed. They included an office based and portable field based system. A rigorous testing regime was conducted to explore the achievable range using Direct IP, the repeatability of position on an established baseline and the time taken to achieve a fixed solution at certain distances.
Other experiments included testing against existing CORS and exploration into design aspects of a portable field solution. The final part of this project discussed the application of the technology to the surveying industry, particularly issues of reliability, cost and quality control.
The experiments conducted found that the use of Direct IP with the ProMark3 proved to be a successful alternative for transmission of differential corrections. Through the use of the internet and mobile phone technology, correction data could be received well beyond 10km, accuracy was well within the
acceptable limits of single frequency RTK and times taken to achieve a fixed solution between base and rover were fast and efficient proving that the use of Direct IP is a great alternative to radio communication.
ไม่มีความคิดเห็น:
แสดงความคิดเห็น