Thesis (M.M. (ICT Policy and Regulation))--University of the Witwatersrand, Faculty of Commerce, Law and Management, Graduate School of Public and Development Management, 2013. / Radio frequency spectrum, a scarce national strategic asset, has not enjoyed the necessary attention and protection it deserves. Spectrum has been managed by the same approach over the last two decades and it is only recently that attention has been given to it due to the pressure of increased competition and technological advancements. The purpose of this study was to explore the policy and regulatory approaches to the management of radio frequency spectrum prevalent in South Africa today. Internationally there is a shift from the traditional command and control spectrum management approaches to more market-based mechanisms, such as auctions and spectrum trading. The South African approach has been marked by delays in the usage of spectrum as a result of the current institutional arrangements where there is an apparent overlap between the policy and regulatory function. The study concludes that the delays could be circumvented by separating the spectrum allocation and assignment into policy and regulatory functions respectively. Efficient spectrum management policy and regulation is important for the next stage of electronic communications revolution because of the advances in the technology such as broadband and agile radio.

This dissertation aims to evaluate the allocation of essential facilities and / or scarce resources in the telecommunication industry in terms of the abuse of dominance provisions under the Competition Act 98 of 1998. Chapter 1 sets the scene by setting out the history of competition law in South Africa, and the policy considerations that lead to the promulgation of the Competition Act 98 of 1998 in its current form. This is followed by a brief examination of the scope, purpose and application of the Act, including the conduct regulated by the Act. Chapter 1 explores the functions of the Competition Authority in South Africa, and the various enforcement bodies created under the Act. In order to provide context, and to introduce the telecommunication industry, the dissertation briefly discusses concurrent jurisdiction between the Competition Authority and the Telecommunication Regulatory Authority (ICASA). Chapter 1 concludes with a description of radio frequency spectrum; and sets out the scope of the dissertation. Chapter 2 sets out the market definition for radio frequency spectrum, which is defined broadly as the national product market for radio frequency spectrum. The dissertation is limited to the telecommunication industry, thus the market definition is defined only within the context of this industry. After setting out the market definition and identifying the key players in the market for radio frequency spectrum in the telecommunication industry, the dissertation proceeds to discuss the abuse of dominance provisions under the Competition Act, the essential facilities doctrine and scarce resources under the Act. This discussion includes a description of how the doctrine of essential facilities was introduced into our law, a discussion of the relevant case law and a comparative approach of the status in the European Union and the USA. The concept of abuse of dominance and its application in South Africa, the European Union and the USA is described. In conclusion, Chapter 3 compares essential facilities and scarce resources. It is submitted that radio frequency spectrum is a scarce resource and should be dealt with under the abuse of dominance provisions of the Competition Act. Chapter 4 analyses the allocation of radio frequency spectrum in South Africa. It describes the Regulatory Authority and the empowering provisions under the Electronic Communications Act, under which ICASA is empowered to allocate radio frequency spectrum, including the recent policy directions of the Department of Communication. A discussion of the various competition issues that could influence the allocation of radio frequency spectrum follows, specifically with regard to the recent policy directions of the Department of Communications. A brief summary of the views of some of the main industry players in South Africa on the policy directions sets out the concerns of the industry in general, and their reaction to the policy directions. In the concluding Chapter, it is submitted that the abuse of dominance provisions of the Competition Act should be applicable to the allocation of radio frequency spectrum. The reason for this statement is that ICASA often obtains a de facto dominant position with regard to the allocation of an essential facility and / or a scarce resource, such as radio frequency spectrum. Thus it is submitted that the regulator is in a position of dominance which allows it to use regulation as a tool to act anti-competitively. The final Chapter concludes that a wider interpretation of the abuse of dominance provisions is necessary to ensure fair and efficient allocation of radio frequency spectrum. A brief discussion of the policy directions suggests that although, on the face of it, the directions are in line with the provisions of the Competition Act, the method of allocation has scope for anti-competitive allocation by a de facto dominant regulatory authority. It is submitted that more attention must be paid to the actual methods of allocation of radio frequency spectrum, and that a fine balance is required to ensure that spectrum allocation is transparent and efficient. In closing, the dissertation mentions the Electronic Communications Amendment Bill (Government Gazette No. 35525 18 July 2012), which aims to introduce a Spectrum Management Agency to oversee the allocation of radio frequency spectrum in the future. / Dissertation LLM --University of Pretoria, 2014 / am2014 / Mercantile Law / Unrestricted

We propose an original analog method to perform instantaneous and quantitative spectral analysis of microwave signals. An ensemble of nitrogen-vacancy (NV) centers held in a diamond plate is pumped by a 532 nm laser. Its photoluminescence is imaged through an optical microscope and monitored by a digital camera. An incoming microwave signal is converted into a microwave field in the area of the NV centers by a loop shaped antenna. The resonances induced by the magnetic component of that field are detected through a decrease of the NV centers photoluminescence. A magnetic field gradient induces a Zeeman shift of the resonances and transforms the frequency information into spatial information, which allows for the simultaneous analysis of the microwave signal in the entire frequency bandwidth of the device. The time dependent spectral analysis of an amplitude modulated microwave signal is demonstrated over a bandwidth of 600 MHz, associated to a frequency resolution of 7MHz , and a refresh rate of 4 ms. With such integration time, a field of a few hundreds of lW can be detected. Since the optical properties of NV centers can be maintained even in high magnetic field, we estimate that an optimized device could allow frequency analysis in a range of 30 GHz, only limited by the amplitude of the magnetic field gradient. In addition, an increase of the NV centers quantity could lead both to an increase of the microwave sensitivity and to a decrease of the minimum refresh rate down to a few ls.

Au début des années 2000, les instances aéronautiques ont exprimé le besoin de développer un nouveau système de radiocommunication aéronautique du fait de l'augmentation du trafic aérien et de la saturation croissante des capacités de communication radio entre les aéronefs et les stations de contrôle aérien. L'une des composantes de ce système, nommée L-DACS (« L-band Digital Aeronautical Communication System »), devrait opérer dans la bande L-aéronautique (960-1164 MHz), dans laquelle fonctionnent également de nombreux autres systèmes radioélectriques. La compatibilité radioélectrique (CRE) de L-DACS avec ces systèmes est un des facteurs principaux à prendre en considération dans le développement d'un tel système.L'objectif principal de cette thèse est d'identifier les principaux problèmes reliés à la CRE et d'en étudier les cas critiques. Ces travaux sont fondamentaux en aéronautique, puisque tout dysfonctionnement dans la communication ou dans les systèmes de radionavigation peut mettre en danger la sécurité du vol. Les conclusions de cette thèse contribueront à la normalisation du système L-DACS et à la finalisation de ses spécifications.Dans une première étape, on étudie l'état de l'art dans les communications aéronautiques et en CRE. On analyse en particulier les dernières spécifications des deux systèmes candidats L-DACS. Ensuite, on propose un algorithme de calcul de brouillage dans le but d'étudier la CRE dans le domaine fréquentiel, d'en identifier et d'en traiter les cas critiques. L'analyse fréquentielle étant insuffisante dans plusieurs cas, on propose alors une approche temporelle d'étude de CRE. Après en avoir présenté les avantages, on présente un exemple d'étude de l'effet d'un système L-DACS sur un récepteur DME (« Distance Measuring Equipment ») à l'aide d'un banc de test CRE aéronautique.Cette thèse a été réalisée en collaboration avec la Direction Générale de l'Aviation Civile (DGAC), qui est un acteur principal pour la réglementation des communications et un affectataire de fréquence pour le spectre aéronautique en France. La thèse contribue aux études menées par la DGAC à l'échelle nationale et internationale.Dans les perspectives, on propose la poursuite de cette étude par une approche temporelle plus générale pour étudier la CRE entre des systèmes radioélectriques quelconques en tenant compte de paramètres supplémentaires liés à la dynamique des systèmes et aux propriétés de leurs technologies. / In the beginning of the 21th century, the aeronautical authorities expressed their need to develop a new system for aeronautical radiocommunications, because the air-traffic is increasing and that current communication systems between pilots and air-controllers are reaching their capacity limits. The L-band Digital Aeronautical Communication System (L-DACS) is the part of the future system that will be operating in a part of the aeronautical L-band (960-1164 MHz), already occupied by a large number of radio-frequency legacy systems. Consequently, it is essential to consider its radio-frequency compatibility (RFC) for the development of the future L-DACS system. This thesis aims at identifying the principal issues related to RFC and studying its critical situations. Such topics are fundamental in aeronautics, as any communication or radionavigation dysfunction may endanger flight and passengers security. Some obtained results will be used for the L-DACS standardization and its specifications finalization. We first analyze the state-of-the-art in both aeronautical communications and RFC, focalizing on updated specifications of both preselected L-DACS candidate systems. We then propose a deterministic algorithm to compute the interference level in order to study the RFC in the frequency domain under identified critical scenarios. Since the frequency-domain analysis seems to be insufficient in several cases, we develop a different methodology, called the time-frequency approach, to analyze the RFC for such situations. We apply this new approach to analyze the effect of an L-DACS interferer on a Distance Measuring Equipment (DME) receiver, using an aeronautical RFC test-bed that we implemented at SUPELEC. This work has been performed in collaboration with the French Civil Aviation Authorities (DGAC), which are an important actor in aeronautical communication regulations and aeronautical spectrum management in France. The thesis contributes to DGAC studies at national as well as international levels. For further work, we suggest to generalize the proposed time-frequency approach to analyze the RFC between any two radio-frequency systems, taking into account additional parameters related to system dynamics and their technology properties.