Leveraging On GNSS Continuously Operating Reference Stations (Cors) Infrastructure For Network Real Time Kinematic Services In Nigeria

Abstract

Nigeria, in the past five years has established about fifteen (15) Global Navigation Satellite System (GNSS) Continuously Operating Reference Stations (CORS) across the country. The CORS network is primarily meant for the implementation of African Geodetic Reference Frame (AFREF) and Zero-order Geodetic Controls for Nigeria. This GNSS CORS infrastructure provides a viable and highly scalable platform for the implementation of wide range Real Time Kinematic (RTK) services for relevant user communities in Nigeria.  However, the current network architecture and post processing system of the CORS infrastructure does not meet the multi-level application needs in the country. In order to scale down the GNSS application opportunity, there is need for the implementation of this RTK Network with Central Processing Facility (CPF), where the pre-processing, detection and repair of cycle slips, and double difference ambiguities between the reference stations are determined. Thereafter, local error modeling algorithms are derived and transmitted to the users epoch by epoch or at predefined time intervals in the fields. This paper therefore aims at developing this RTK Network Service implementation model for Nigeria, leveraging on the existing Zero-order GNSS CORS Network. The developments of GNSS Infrastructure in Nigeria and existing capacity for viable Network RTK implementation were examined.  The requirements and feasibility of RTK services in Nigeria were identified, and a Network RTK Service Model was developed. The benefits and potential challenges in this RTK Network Services in Nigeria were identified, and recommendations on network densification architecture and implementation strategies for service sustainability and returns on investment were made.  

Keywords: GNSS, CORS, Real Time Kinematic Services, Investment, Sustainability