All for a great CORS!

CORS: an acronym for Continuously Operating Reference Stations

It is hard to imagine, 12 months have passed since the opening day (11/21/2019) of the DPWH Corsnet at the Cavite DPWH District office. 

The opening was attended by engineers from the Bureau of Design, DPWH Head Office and representative engineers from all the offices where CORS were installed.

Dindo Masbate, DPWH BOD addressed the gathering explaining the relevance and importance of the venture.

Engineers brought their GNSS Rovers and connected to the network making the day fun, informative and successful.

The DPWH Corsnet network is an important infrastructure project. Many months of planning and design went into the project. Professionals from the Philippines and overseas were consulted in CORS design ensuring a practical, modern, future proof design.

Elliott Enterprises technical team offered support and experts to assist in the design process. The complete network will require 65-100 CORS stations strategically placed to provide a triangular network across the Philippines. 

In April 2019, Elliott Enterprises were successful in their bid to supply and install Phase One (8 stations plus CORS management software) of the Corsnet.

Utilizing experience within the Elliott Enterprises team, plus assistance from external consultants the network was designed and installed to specification; on time.

The most difficult process was to find suitable buildings with uninterrupted access to the sky (satellites). Members of the BOD and Elliott Enterprises technical team spent three weeks travelling to nearly every regional and district office across mid and southern Luzon searching for the best locations. 

At each site a UAV was used to provide an eye in the sky as the best locations with no trees or buildings to obstruct the antennas from a 360 degree by 180 degree view of the satellites were select.

The project had challenges but was installed on time and everything was in place and tested before the CORVID19 virus closed the country down for travel.

The CORS stations include the Septentrio PolaRx5e CORS receiver, the receivers are specifically designed for CORS networks. The receivers are especially well suited to longer baselines (distance between installations). The receivers were designed to accurately track satellites at the horizon. This allows stations to be installed at 75-120 kilometer network intervals. As costs continue to increase it is important to utilize the best technology to develop an effective, practical network.

As CORS is categorized as critical infrastructure each station uses energy from a solar panel with a smart controller and charging system to provide backup from the grid. This allows 10-20 days operation where natural disasters cause power outages. GNSS correction is still available.

The CORS antennas and monuments are attached to Regional or District office buildings providing stability beyond the Tier 3 CORS specifications. Geo++ reported the antennas were very stable considering the height of the buildings.

Phase One (2019) included 8 stations across the southern areas of Luzon. The network proved successful.

The stations are connected via the Intranet to the DPWH Central Office. The correction software is located on the cloud allowing the expansion and demand for computing to be managed into the future. The CORS software (GNSMART) was installed by Geo++, a German software company providing leading edge GNSS correction   technology well into the future.