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No / This work presents a novel broadband monopole antenna for digital video broadcastingterrestrial (DVB-T) application. The proposed antenna consists of a grating patch and a concave rectangular ground plane with defected ground plane, and the Multiple Split-Ring Resonator (MSRR). The added part in the ground plane and the meta-material are used to enable the antenna height reduction for fixed ranges of operating frequency. The antenna can operate from 468 MHz to 894 MHz frequency range corresponding to 62.5% of impedance bandwidth for |S11|<-7.5 dB. Details of the proposed antenna designs and experimental results of the constructed prototypes are presented and discussed.

This thesis consists of two parts. Part one includes the design procedure and implementation of the building blocks for an RF tuner module used in the Digital Video Broadcasting ¡V Terrestrial ¡]DVB-T¡^system. It contains the comparison of several RF tuner architectures, frequency planning, and link-budget analysis. Measurement results for the designed tuner operating in the frequency range from 50 to 860 MHz show that the maximum power gain ranges from 49 to 57.6 dB. The entire range for gain control is over 60 dB. In the maximum gain state, the noise figure ranges form 6.8 to 11.5 dB, the output third-order interception point¡]OIP3¡^ranges from 11.7 to 13.8 dBm, and the image rejection is over 50 dB. By applying the simplified single-carrier modulation signals, the tuner can pass the DVB-T system specifications with respect to the adjacent-channel and overlapping-channel protection ratios. In part two, an RFIC design for low-noise variable-gain amplifier that can be used in the RF front end of DVB-T system is presented. It operates from 100 to 900 MHz and dissipates 59.4 mW under a 3.3-V power supply. In the maximum gain state, measurement results for this RFIC show that the noise figure is less than 4 dB, the maximum gain is more than 14 dB, and the OIP3 is about 6.8dBm. The entire gain control range is over 40 dB.

The topic of this thesis presents a digital front end (DFE) of the digital video broadcasting over terrestrial (DVB-T). The DVB-T system is similar to most of the prior digital communication system. It is roughly divided into two major parts, one for channel coding/decoding, and the other for modulation/demodulation. The thesis is mainly focused on the DVB-T digital video broadcasting demodulation part of the receiver and the integration of a complete digital front demodulation system. The major operational processor of the DFE is a 2K/8K dual-mode FFT processor, which has been implemented by the TSMC ( Taiwan Semiconductor Manu-facturing Company ) 0.35um 2P4M CMOS process technology to justify the simulation results as well as the correctness of the proposed architecture.

This thesis includes two topics. The first one is a low-power double-edge triggered flip-flop.The other is a orthogonal frequency division multiplex (OFDM) demodulator compliant with the Digital Video Broadcasting Handheld (DVB-H). Low-power double-edge triggered flip-flop (DETFF) is based on multi-Vth transistors technique. Since low threshold voltage transistors are able to generate large leakage current, they are suitable to drive big loads. By contrast, high threshold voltage transistors are more appropriate to latch data due to their low leakage. Therefore, a single latch double-edge triggered flip-flop utilizing multi-Vth transistors can be a low power and high speed design without paying the price of large area. The proposed OFDM demodulator is compliant with the DVB-H standard. The received DVB-H signal is processed by an RF front-end and the following analog-to-digital converter. Then, the digital signal is fed into the demodulator to adjust and calibrate the frequency, timing offset and channel estimation. The proposed DVB-H demodulator is mainly composed of five blocks : symbol timing synchronization block, carrier frequency offset compensation block, fast Fourier transform block, scatter pilot detection block and channel compensation block.

H παρούσα πτυχιακή εργασία επικεντρώνεται αρχικά, στη μελέτη των προτύπων της επίγειας και φορητής ψηφιακής τηλεοράσης (DVB-T και DVB-H). Το DVB-T αποτελεί τo πρότυπο της επίγειας µετάδοσης που έχει αναπτυχθεί µε ιδιαίτερα πολύπλοκο τρόπο από ότι τα προηγούµενα πρότυπα για δορυφορική και καλωδιακή µετάδοση. Με το DVB-T επιτυγχάνονται καλύτερες επιδόσεις απ’ ότι µε την αναλογική μετάδοση και προσφέρει πολλά πλεονεκτήµατα στην επίγεια µετάδοση αλλά και λήψη του σήµατος. Επειδή αποδείχθηκε σχετικά νωρίς ότι το DVB-T έχει μειονεκτήματα σε ότι αφορά το broadcasting τηλεοπτικού σήματος σε κινητά τηλέφωνα, γεννήθηκε η ιδέα για ένα σύστημα αποκλειστικά για φορητές συσκευές βασισμένο στο DVB-T. Καλείται DVB-H (DVB-Handheld). Δεδομένου ότι τα συστήματα ψηφιακής μετάδοσης DVB-T και DVB-H χρησιμοποιούν για τη διάδοσή τους το επίγειο και δορυφορικό κανάλι, γίνεται εκτενής ανάλυση των παραμέτρων που επηρεάζουν την επίγεια και δορυφορική μετάδοση, κυρίως από την οπτική των απωλειών. Στη συνέχεια, γίνεται ανάλυση όλων των σταδίων που λαμβάνουν χώρα κατά την εκπομπή και λήψη ενός OFDM σήματος μέσω ενός φυσικού καναλιού, διαμόρφωση η οποία χρησιμοποιείται κατά κόρον στα πρότυπα DVB-T και DVB-H. Έπειτα, προσομοιώνουμε μέσω του MATLAB όλη τη διαδικασία της OFDM μετάδοσης και λήψης, εξάγοντας τις γραφικές παραστάσεις με τη μορφή του OFDM σήματος σε κάθε στάδιο. Τέλος, θα μελετήσουμε την επίδραση του ασύρματου καναλιού (δορυφορικού και επίγειου) στην εξασθένηση του OFDM σήματος, στο σταθμό λήψης και θα εξάγουμε τις γραφικές παραστάσεις, επιβεβαιώνοντας την εξασθένηση αυτή. / This project focuses initially on the study of patterns of terrestrial and mobile digital television (DVB-T and DVB-H). The DVB-T standard is the terrestrial broadcasting standard that has been developed in a very complex way than previous standards for satellite and cable broadcasting. By implementing DVB-T we can achieve much better performance than analog transmission as it offers many advantages for terrestrial transmission and reception. Since it has been proved early on that the DVB-T has disadvantages in terms of the broadcasting of television signals to mobile phones, there has been created an idea for a system that exclusively focuses on mobile devices, based on DVB-T. It is called DVB-H (DVB-Handheld). Since the digital broadcasting systems of DVB-T and DVB-H use the terrestrial and satellite channel to transmit information, an extensive analysis of parameters affecting the terrestrial and satellite transmission takes place, mainly from the perspective of losses. Then, there takes place an analysis of all stages that occur when transmitting and receiving an OFDM signal through a natural channel, modulation which is widely used in DVB-T and DVB-H. Then, we run a MATLAB simulation for the whole process of OFDM transmission and reception, exporting graphs of the form of the OFDM signal at each stage. Finally, we will study the effect of wireless channel (satellite and terrestrial) as far as the weakening of the OFDM signal is concerned at the receiving station and we will export the graphs, confirming the aforementioned attenuation. .

M. Ing. / Digital Video Broadcasting-Handheld (DVB-H) is a technology that enables the reception of television services/programmes on a specific mobile handheld device. MultiChoice Subscriber Management Services (Propriety) Limited, in the year 2006, commenced a project in South Africa; to deploy a trial DVB-H network. The initial phase of the project included the major cities, namely Johannesburg, Cape Town and Durban. The trial network deployed in South Africa assisted MultiChoice in optimizing the efficiency and reliability of the system. It was at this stage that MultiChoice decided to deploy the DVB-H network in other parts of Africa. MultiChoice soon applied for frequency licenses in Nigeria, Kenya and Namibia. These licenses would enable MultiChoice to operate the DVB-H networks on a commercial platform in those countries; and would also enable MultiChoice to start generating an income by providing this service. Shortly after being awarded a license to broadcast DVB-H, a commercial DVB-H network was launched in Kenya in April 2007. The network consisted of two broadcast sites, at the time. MultiChoice came to an agreement with one of the local Mobile Network Operators (MNO) in Kenya to assist MultiChoice in getting the mobile television handset to the Kenyan people. The MNO possessed the required customer base and also the correct billing infrastructure. An immediate concern was raised by the MNO, about the DVB-H network coverage. With DVB-H, portable outdoor network coverage is guaranteed; however, to obtain coverage inside a building, can be somewhat problematic, especially if that building consists of two or more walls. It will be difficult for the DVB-H signal to penetrate those walls. The MNO’s retail outlets were mostly situated in shopping centre type buildings, hence, the MNO put forward a request for coverage inside the outlets where the mobile handset will be sold. This means that network coverage inside these shopping centre type buildings was required. Therefore, an indoor broadcast system was required in order to obtain the required coverage inside the building. MultiChoice decided to undertake a project to design and build this type of system for the current trial DVB-H network deployed in South Africa. This project would be used as a case study for future projects to be implemented for the network in Kenya. In order to successfully implement an Engineering related project, it is essential to consider both the Project Management aspects and the Engineering Management aspects of that particular project. These two concepts are very closely linked and should not be considered individually when implementing an Engineering project. It is understood that all projects go through certain life cycle phases in some form or other. This document provides the background theory to the four commonly recognized phases of the Project Life Cycle, it is then further shown how various aspects of these life cycle phases were applied to the actual project; and how the implementation of these aspects could improve project performance in the future. Some Engineering Management principles are also discussed and shown how they were applied to the actual project. Elements of this case study shall provide useful information for the projects to be implemented in Kenya.

The first topic of this thesis presents a bus driver design which is based on a charge recycle technique. The proposed design is mainly composed of a differential low swing circuit and a charge recycling circuit. The differential low swing signaling has been adopted to achieve low power and robust data transmission. The charge recycle is utilized to reduce power dissipation on long lines for the differential low swing signaling. The second topic is the coded orthogonal frequency division multiplex demodulation (COFDM) demodulator compliant with the European digital video broadcasting over terrestrial (DVB-T). It can recover the frequency offset of COFDM signal and dynamically select the FFT stages to synchronize the start of a symbol. The proposed design mainly contains four blocks : a time synchronization block, a frequency synchronization block, a 2K/8K FFT processor, and a channel estimation block.

The inherent broadcast nature of satellites, their global coverage and direct access to a large number of subscribers give satellites unrivalled advantages in supporting IP multicast applications. A new generation of satellite systems that support regenerative on-board processors and multiple spot beam technology have opened new possibilities of implementing IP multicast communication over satellites. These new features enable satellites to make efficient use of their allocated bandwidth resources and provide cost effective network services but equally, create new challenges for mobile satellite terminals. IP mobility support in general and IP mobile multicast support in particular on mobile satellite terminals like the ones mounted on continental flights, maritime vessels, etc., still remain big challenges that have received very little attention from the research community. Up till now, there are no proposed mechanisms to support IP multicast for mobile receivers/sources in multi-beam satellite networks in open literature. This study explores the suitability of IP multicast mobility support schemes defined for terrestrial networks in a satellite environment and proposes novel schemes based on the concepts of Home and Remote subscription-based approaches, multiple interface and PMIPv6 protocol. Detailed analysis and comparison of results obtained from the proposed schemes, Mobile IP (MIP) Home and Remote subscription-based approaches (for terrestrial networks) when implemented on a reference multi-beam satellite network are presented. From these results, the proposed schemes outperform the MIP Home and Remote subscription-based approaches in terms of gateway handover latency, number of multicast packets lost and signalling cost over the satellite air interface.