What is Geodetic Network and how it works

The Rwanda Geodetic Network (RGN), is a network of Continuously Operating Reference Stations (CORS) that provide Global Navigation Satellite System (GNSS) data consisting of carrier phase and code range measurements in support of three dimensional positioning, meteorology, space weather and geophysical applications throughout the Rwanda, its neighboring countries.

Surveyors, GIS users, engineers, scientists, and the public at large that collect GNSS data can use GNSS CORS data to improve the precision of their positions. CORS enhanced post-processed coordinates approach a few centimeters relative to the National Spatial Reference System, both horizontally and vertically.

The CORS network is a multi-purpose cooperative endeavor involving government, academic, and private organizations. The sites are independently owned and operated. Each agency shares their data with RGN, and RGN in turn analyzes and distributes the data free of charge.

Where are these GNSS CORS sites located?

Currently, we have 10 CORS sites in Rwanda as iondicated in the table below and you can find them online through this link: https://corsmap.com/location/rwanda/

CORS SITE NAME

CORS SITE CODE

LOCATION

Kigali

KGLI

Rwanda Development Board (RDB).

Musanze

MSZE

UR-BUSOGO Campus

Huye

HUYE

UR-Huye campus

Bugesera

BUGE

Bugesera district head office

Kayonza

KAYO

Kayonza district head office

Kirehe

KRHE

Kirehe district head office

Nyagatare

NGTRE

Nyagatare district head office

Karongi

KRNG

Karongi district head office

Rubavu

GISE

Rubavu district head office

Rusizi

RSZI

Rusizi district head office

Figure2 Shows the Map of 10 GNSS CORS Stations.

Why GNSS CORS stations?

Nowadays the time of GPS or even GNSS static baseline determination is almost out-of-date for everyday applications. The present trends are to continuously observe and measure using GNSS, install permanent GNSS base stations or networks and provide real time accurate positioning

If you put these three trends together you have an advanced component of geoscience infrastructure known as a GNSS CORS network. These networks need to have a geodetic datum, meaning that they have to be linked to the available terrestrial reference frames. Such GNSS CORS networks are or will be the primary means by which numerous users can access and realize position that is based on a geodetic datum.

Who manages this network?

This network owned, maintained and operated by Rwanda Land Management and Use Authority (RLMUA) but despite the effort made, we have main challenges in maintaining those CORS sites and one of them are:

CORS Network Density: The setup of a CORS site is quiet expensive and to have them enough is costly. As we said above, we only have 10 sites, Power instabilities: The power instabilities bring a lot of risks such as damaging some sensitive equipment hence cutting off the sites, insufficient skills for the users and inefficient system sustainability, etc.

To overcome all those challenges, the Rwanda Land Management and Use Authority is trying to engage the private sector to partner to run the network efficiently and sustainably, is also enhancing the capacity of the employees and users and searching for funds in order to increase the number of sites to ensure a more accurate measurements.