The use of GPS is becoming increasingly popular for real-time navigation systems. To ensure that satellite failures are detected and excluded at the receiver is of high importance for the integrity of the satellite navigation system. The focus of this paper is to implement a fault detection and exclusion algorithm in a software GPS receiver in order to provide timely warnings to the user when i...

Körner and Marton established the capacity region for the 2-receiver broadcast channel with degraded message sets. Recent results and conjectures suggest that a straightforward extension of the Körner-Marton region to more than 2 receivers is optimal. This paper shows that this is not the case. We establish the capacity region for a class of 3-receiver broadcast channels with 2-degraded message...

This work propose a new Kalman filter-based method for integrity monitoring, following the solution separation approach of the Advanced Receiver Autonomous Integrity Monitoring (ARAIM) algorithm. This method evaluates the separation of state correction using different subsets of measurement to detect abnormalities as well as potential faulty satellites for exclusion. This approach differs from ...

We consider a land mobile satellite communication system using spread spectrum techniques where the uplink is exposed to MT jamming attacks, and the downlink is corrupted by multi-path fading channels. We proposes an anti-jamming receiver, which exploits inherent low-dimensionality of the received signal model, by formulating a robust principal component analysis (Robust PCA)-based recovery pro...

This paper presents the architecture of a DVB-S2 receiver prototyping environment that is based on software defined radio techniques. DVB-S2 comprises the newest European standard for broadband satellite communications. The software defined radio approach enables the adaptation of the receiver to different operational modes e.g. CCM, VCM, ACM, and the support of multiple services. The prototypi...

This paper shows a lightweight technique for extending the positioning capabilities of a global navigation satellite system to areas characterized by reduced satellite visibility. This technique includes the presence of a WiFi coverage, used to implement the virtual satellite concept. In particular we assume that a customer terminal can receive both Global Positioning System (GPS) signals and W...

GAGAN is an Indian implementation of Satellite Based Augmentation System (SBAS), developed jointly by Airports Authority of India (AAI) and Indian Space Research Organisation (ISRO). It is in final operational phase with all the required ground and space segments ready. With the availability of GAGAN signal-in-space (SIS), the improvement in position solution is investigated using the two collo...

Genetic programming (GP) can automatically fuse given classifiers of diverse types to produce a combined classifier whose Receiver Operating Characteristics (ROC) are better than [Scott et al.1998b]’s “Maximum Realisable Receiver Operating Characteristics” (MRROC). I.e. better than their convex hull. This is demonstrated on a satellite image processing bench mark using Naive Bayes, Decision Tre...

How to cite this article: Botai CM, Combrinck L. Global geopotential models from Satellite Laser Ranging data with geophysical applications: A review. S Afr J Sci. 2012;108(3/4), Art. #662, 10 pages. http:// dx.doi.org/10.4102/sajs. v108i3/4.662 The launch of artificial satellites (as early as in 1957), specifically the launch of the first laser tracked satellite, Beacon-B, in 1964, has provide...

A random beacon periodically outputs a random number and was introduced by Rabin[12] to secure remote transaction. We consider a random beacon that is pervasive in the sense that, it is available everywhere, and accesses to the beacon blends with normal activities. With a pervasive beacon, it is difficult to disrupt the beacon and detect accesses to it. As a result, the pervasiveness of the bea...