Στην παρούσα διπλωματική εργασία γίνεται διερεύνηση των βέλτιστων τεχνικών παραμέτρων σχεδιασμού υβριδικής τηλεπικοινωνιακής πλατφόρμας για την υποστήριξη της υπηρεσίας DVB-H μέσω δορυφόρου. Γίνεται μοντελοποίηση των δύο τύπων μεταδόσεων, επίγειας και δορυφορικής. Τα αποτελέσματα που εξάγονται από τις προσομειώσεις συγκρίνονται με στοιχεία που καθορίζουν πρότυπα του ΕTSI. / In this thesis are worked out the optimised parameters for the design of an hybrid platform which supports the DVB-H (Digital Video Broadcasting for Handheld devices)service via satellite. Two kinds of broadcasting are modelled, terrestrial and satellite. The results of the simulation of these models are compared with elements which are defined by ETSI standards.

Zugl.: Braunschweig, Techn. Univ., Diss., 2009

This thesis includes two topics. The first topic is a ZigBee transceiver used in 2.45 GHz band design. The second topic is a 2K/4K/8K multimode fast Fourier transformation ( FFT ) for DVB-H demodulators. The first topic includes simulations and hardware design. The chip is a physical layer design compliant with IEEE Std 802.15.4 standard, including a transmitter and a receiver for 2.45 GHz band. The measurement of the maximum power on silicon is about 731 £gW at 8 MHz. It is proved to be compliant with the low power consumption requirement specified by the standard. The second topic includes simulations and hardware design of an FFT for DVB-H demodulators. This processor is based on a pipeline architecture with radix-2, radix-22 and radix-23 computation element. We propose one sharing butterfly architecture to be used in the variable length FFT processor.

Zugl.: Braunschweig, Techn. Univ., Diss., 2008

This dissertation addresses the problem of providing a®ordable mobile mul-timedia services in wide area wireless networks. The approach is to con-sider novel system architectures, based on reusing and sharing of the ex-isting network infrastructure for cellular and terrestrial TV broadcastingsystems. The focus has been on the radio resource management techniques,and the evaluation of the potential cost savings, compared to traditionalevolution tracks of the cellular and broadcasting systems.The studies show that deployment cost of a wide area broadcastingnetwork, using DVB-H technology, is very large if high data rate and fullarea coverage is targeted. For this reason we propose to avoid the broad-casting infrastructure dimensioning for full area coverage, and use insteadthe cellular systems to enable error correction for broadcasting transmis-sions. For the special case of mobile users, the chosen approach is to tradesystem's cost and capacity for improved perceived coverage. This trade-o®is enabled by the use of application layer forward error correction, usingRaptor coding.The general purpose Ambient Networks technology was chosen to en-able a platform for inter-operability between cellular and broadcasting sys-tems, especially the necessary interfaces. Under the Ambient Networksframework, we investigate the achievable cost savings o®ered by a hybridcellular-broadcasting system when combinations of broadcast and point-to-point transmissions are jointly utilized to provide ¯le transfers and stream-ing services. Two cases were investigated: one where the cellular systemacts as a replacement and deliver the data in the areas where broadcastingtransmissions cannot reach, and another one where cellular system carriesparity data to users that experience temporary outage in the broadcastingsystem. The results are encouraging, as they show that ¯le transfer costcan be reduced by more than 50%, but only under certain conditions.On a short term, hybrid cellular-broadcasting systems based on 3G andDVB-H, o®er a good platform for testing new and innovative mobile TVservices, enriched with interactivity and content personalization. From atechnical perspective, the outcomes of the presented studies indicate thatfuture systems built on hybrid cellular-broadcasting infrastructures are ableprovide a long term and cost e±cient solution for delivery of a®ordablebroadband multimedia services to mobile users. However, today's cellularand broadcasting systems live in di®erent worlds, are driven by di®erentrevenue models, and they are now starting to compete, instead of cooperate,for controlling the multimedia delivery channels to mobile users. / QC 20100708

This research aims to design a dual-conversion tuner RFIC for DVB-H applications with EDA tools. In order to have good understanding of the EDA tools used, both time-domain and frequency-domain simulation techniques are studied and discussed in this thesis. The designed tuner RFIC is implemented by a TSMC 0.35£gm SiGe BiCMOS process. The parasitic effects from PCB interconnects are also considered in this work. We use 3-D quasi-static EM simulation tool to extract the parasitic elements for PCB interconnects, and co-simulate these parasitic elements with RFICs using circuit simulation tool. The implemented tuner RFIC integrates most key components into a single chip, including the variable-gain low noise amplifier, up-converting mixer, intermediate-frequency amplifier, and down-converting mixer. Under QPSK modulation test, the designed tuner RFIC shows a wide dynamic range with good protection ratio. In addition, it has a low power consumption and thus is suitable for use in portable digital TV equipments.

This thesis is composed of three parts. The first part surveys the literature on RF architecture and semiconductor process technology in the DVB-H tuner applications. The RFIC design considerations are also discussed. In the second part, the DVB-H tuner RFIC design using TSMC 0.18£gm RF CMOS technology is presented. Discussions between simulated and measured results of each circuit stage are also included. In the third part, the RFIC testing results for CW and DVB-H input signals are demonstrated. For a QPSK signal with 8MHz bandwidth and 7/8 code rate, the sensitivity of the RFIC can reach -87dBm. The adjacent channel protection ratio can meet the specification. The chip power consumption is 70.2mW, and the chip size is 1.96 mm2.

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.

Satellite networks provide an alternative to terrestrial networks where cost and lack of infrastructure are driving parameters. For a satellite network to be cost effective one needs to be able to increase the efficiency of the network: this is accomplished by focusing on the parameters that affect the performance of the system and improving on them where possible. The factors affecting the network performance include the capacity, the propagation delay, the protocol used, and the channel error rate, among others. There are various ways to implement a satellite network depending on the satellite orbit, the architecture used, the access technique used, the radio interfaces used, etc. This thesis work describes the chosen satellite standard, Digital Video Broadcasting – Return Channel via Satellite (DVB-RCS) and the associated Medium Access Control (MAC) protocols. Two protocols were designed and investigated under ideal channel conditions, these being the Combined Free/Demand Assigned Multiple Access with Piggy Backing – Packet Dropping (CF/DAMA-PB-PD) protocol; and the Combined Free/Demand Assigned Multiple Access with Piggy Backing – Prioritised Earliest Deadline First (CF/DAMA-PB-PEDF) protocol, both derived from the Combined Free/Demand Assigned Multiple Access with Piggy Backing (CF/DAMA-PB) protocol. The multimedia traffic models for voice, video and web classes are described, validated through simulations and presented; these provide the heterogeneous vi traffic required for evaluating the performance of the satellite system implemented and the designed protocols. Under the multimedia traffic, CF/DAMA-PB-PD was shown to excel in average packet delay reduction while reducing the overall system throughput. The CF/DAMA-PB-PEDF does not contribute to an improvement over the CF/DAMA-PB-PD protocol. The effects of a non-ideal channel on the CF/DAMA-PB-PD protocol was investigated and presented along with the design of three MAC protocols that take the channel characteristics into account to improve on the system performance. The cross-layer interactions, more specifically the interaction between the physical and data–link layers, were used, investigated and presented. The channel state information in terms of signal-to-noise ratio (SNR) was used to improve the system performance. The five protocols evaluated under non-ideal channel conditions were the CF/DAMA-PB, CF/DAMA-PB-PD, CF/DAMA-PB-BSNRF, CF/DAMA-PB-DD and the CF/DAMA-PB-BSNRF+DD. The best overall performance, both in average packet delay while maintaining good QoS levels and throughput was shown to be that of the CF/DAMA-PB-DD protocol. / Thesis (M.Sc.Eng.)-University of KwaZulu-Natal, Durban, 2010.

Project is focused on description DVB broadcasting for hand-held’s. It describes standard DVB-H that is founded on DVB-T and uses its transmission infrastructure. Standard DVB-SH is a hybrid system that adds to terrestrial broadcasting satellite connection. Signal can extend by various environments, therefore it are defined models transmission channel with defined parameters. Simulation of the transmission in both channel are realized in user application created in MATLAB. Finally, obtained results are evaluated and discussed.