No description available.

No description available.

<p>CMMB (China Multimedia Mobile Broadingcasting) is a wireless broadcastingchannel standard for low bandwidth, low cost hand-held digital TV is adopted byall continental Chinese government TV broadcasting companies and some HongKong private TV broadcasting companies. The business potential is high, yet thefuture is hard to predict because it might be replaced by GB200600 or DTMB. Thedigital modulation is based on OFDM with pilot supporting channel estimationand equalization and CP supporting multi-path induced ISI problems.This thesis investigates the implement a CMMB system using a SDR platform.Simulation chain was implemented using MATLAB with full data precision includingCMMB transmitter and receiver. The transmitter behavior model includes RSencoder, LDPC encoder, OFDM modulation, etc. The receiver behavior modelincludes OFDM demodulation, channel estimation, channel equalization, LDPCdecoder, RS decoder, etc. Different channel models emulating pathloss, whitenoise, multi-path, and glitch were modeled. Based on the simulation chain andchannel models, T-domain, F-domain channel estimator and equalizer were implemented,optimized. Optimized TD-FD models for different mobility scenarioswere proposed. The focus of the thesis is on 2D (FD-TD) channel estimation andequalization.</p>

CMMB (China Multimedia Mobile Broadingcasting) is a wireless broadcastingchannel standard for low bandwidth, low cost hand-held digital TV is adopted byall continental Chinese government TV broadcasting companies and some HongKong private TV broadcasting companies. The business potential is high, yet thefuture is hard to predict because it might be replaced by GB200600 or DTMB. Thedigital modulation is based on OFDM with pilot supporting channel estimationand equalization and CP supporting multi-path induced ISI problems.This thesis investigates the implement a CMMB system using a SDR platform.Simulation chain was implemented using MATLAB with full data precision includingCMMB transmitter and receiver. The transmitter behavior model includes RSencoder, LDPC encoder, OFDM modulation, etc. The receiver behavior modelincludes OFDM demodulation, channel estimation, channel equalization, LDPCdecoder, RS decoder, etc. Different channel models emulating pathloss, whitenoise, multi-path, and glitch were modeled. Based on the simulation chain andchannel models, T-domain, F-domain channel estimator and equalizer were implemented,optimized. Optimized TD-FD models for different mobility scenarioswere proposed. The focus of the thesis is on 2D (FD-TD) channel estimation andequalization.

On 29th February 2000, The Directorate General of Telecommunications, Ministry of Transportation and Communications, announced the result of selection for DAB (Digital Audio Broadcasting) experimental digital broadcasting. From that moment, many FM Radio Stations initiated their DAB digital broadcasting. Compared with FM Radio, AM Radio is slower on initiating digital broadcasting. However, new technology continuously comes out. The integration of media technology has a great influence on the media broadcasting model. The emergence of new media accelerates the decline of traditional media. Earlier emerging than internet, TV and FM Radio industries, how will AM Radio strive for continuance and development? To encourage existing AM Radio in initiating their digital future, the Ministry of Transportation and Communications announced the project of experimental digital broadcasting of IBOC AM and DRM on June 3rd, 2004. It is worth for the research scholars to study how the AM Radio initiates digital broadcasting and what the influential factors are. Therefore, this research is trying to find the factors which turn AM Radio to the digital future, and also discuss what factors will encourage radio enterprenors to initiate digital broadcasting, what kind of digital system is appropriate for AM Radio, and what the situation is for experimental DRM broadcasting in Taiwan. We are trying to find out the factors turning AM Radio to the digital future, and make AM Radio (with declining listening ratio and poor reception quality) improve the performance, as well as create new core value of AM Radio Industry. According to the objective and motivation above-mentioned, we designed and proceeded this research as follows: We started from an investigation on 28 AM Radio Stations in Taiwan to know their needs for digital broadcasting, and then collected data and made statistic analysis based on the questionnaires returned. We also took interviews with professional people assisting in DRM digital broadcasting for AM Radio. Besides, we participated in the World DAB Forum Conference held in Taiwan in this year, and finally went into a conclusion and some suggestions. We found from the information in questionnaires that the factors making AM Radio to initiate digital broadcasting are not precise. However, we know more about how the digital broadcasting is going among AM Radio Stations, from the information collected by interviewing professional people who assist in DRM digital broadcasting for AM Radio. It will bring advantages in competition for AM Radio Stations to initiate digital broadcasting. Thus, it can not wait to turn to digital future. The Radio enterprenors should use technology well and increase additional value. They have to follow the trend, develop new co-operation model, and establish their brand image. They should also enhance on inspection of program contents, and hold success factors. They can increase reception ratio only with fine broadcasting, excellent program contents, good reception quality and perfect marketing strategy. As to the technical people, they need to care about the development on technology, and provide new information for management to make decision. Besides, the policy of government must be precise, in order to encourage Radio enterprenors in initiating digital broadcasting. The above conclusion could be the reference in digital radio research.

The main objective of this thesis was to examine three key questions concerning the political economy of digital broadcasting. First, the concept of digital broadcasting and its regulatory issues were investigated. Following the review of the related theories, I proposed a political economy of digital broadcasting framework as a theoretical perspective. Second, the factors influencing global digital broadcasting were examined. This research has investigated the main factors that influenced the regulatory changes and hardware and software markets around digital broadcasting at a global level. Finally, as a case study, I explore why and how the Korean government introduced digital broadcasting, setting this against the wider background of changing state-market relations. Various stakeholders have been involved in the digitisation of broadcasting at the national and global level. This process follows and forms the changing political economic configuration of the broadcasting industry of the nation-state facing neoliberal globalisation. To achieve the aims, the thesis uses archival research, questionnaire surveys and in-depth interviews. I argue that the digitisation of broadcasting in South Korea has reflected the changing power relationships among state, market and. civil society in democratisation and globalisation. The consumer electronics manufacturers, telecommunication companies and the Ministry of Information and Communication have played pivotal roles in the introduction of digital broadcasting. The public broadcasters, press union and some civic organisations have played alternative roles in the process. In so doing, the role of the state has changed from one of authoritarian market formation to non-authoritarian market formation, market adjustment and coordinating different interests. The Korean state has the contradictory features of a neoliberal state, which has deregulated some areas such as broadcasting, telecommunications and financial markets, and played a role of entrepreneurial government at the same time.

Made available in DSpace on 2015-04-22T22:00:47Z (GMT). No. of bitstreams: 1 jose.pdf: 2255469 bytes, checksum: cebe37770c4719e5ebf2b60e4ae0d2a6 (MD5) Previous issue date: 2013-06-07 / CAPES - Coordenação de Aperfeiçoamento de Pessoal de Nível Superior / Currently, the majority of multicarrier transmission systems are based on the Fourier transform, which is used as frequency multiplexing technique. The main advantages of this approach include multipath immunity and low computational complexity, due to the use of a family of fast algorithms, known as Fast Fourier Transform (FFT). However, when used to provide a robust transmission, this technique presents some disadvantages, like the need for a cyclic prefix, which demands part of the useful datarate. In this work, a study for verifying the possibility of replacing the FFT, by the wavelet transform, was carried out, which has the potential to raise some advantages, such as the removal of the cyclic prefix and a simpler synchronization procedure. A computational model for the transmission layer of the Integrated Services Digital Broadcasting Terrestrial, Brazilian version (ISDB-Tb) was created, aiming to provide a direct comparison between two versions: the traditional one, which is based on FFT, and a new proposal, which is based on wavelets. Such an evaluation was performed through the relation between error bit rate and signal-to-noise ratio, in additive white gaussian noise, Rayleigh and Rician fading and also in frequency-selective Rayleigh fading channels. Similar comparisons were also performed for the ETSI TS 101 475 (HIPERLAN-2) and Digital Video Broadcasting Terrestrial (DVB-T) systems. The simulation results show that the wavelet-based systems present a similar performance, when compared with the FFT-based ones, for the chosen channel models, and without employing a cyclic prefix, which allows a more efficiente spectrum use. / Atualmente, uma grande parte dos sistemas de transmissão multiportadoras é baseada na transformada de Fourier, como técnica de multiplexação em frequência. Dentre as suas principais vantagens, encontram-se a imunidade a multipercursos e a baixa complexidade computacional, através de algoritmos rápidos conhecidos como Fast Fourier Transform (FFT). Esta técnica, entretanto, para proporcionar uma transmissão robusta, apresenta a desvantagem de exigir prefixo cíclico, o que resulta no consumo de uma fatia do espectro útil. Neste trabalho, um estudo para se verificar a viabilidade de substituição da FFT pela transformada wavelet foi realizado, o que promete trazer algumas vantagens, tais como a não exigência de prefixo cíclico e uma sincronização mais simples. Um modelo computacional para a camada de transmissão do Integrated Services Digital Broadcasting - Terrestrial, Brazilian version (ISDB-Tb) foi criado, com o objetivo de proporcionar uma comparação entre duas versões: a atual, baseada em FFT, e uma nova proposta, baseada em wavelets. Tal avaliação foi realizada em termos das curvas de taxa de erro de bit versus relação sinal ruído, em canais com adição de ruído gaussiano branco, com desvanecimento plano de Rayleigh e Rice e também com desvanecimento seletivo em frequência de Rayleigh. Comparações similares também foram realizadas para os sistemas ETSI TS 101 475 (HIPERLAN-2) e Digital Video Broadcasting Terrestrial (DVB-T). Os resultados obtidos mostram que os sistemas baseados em wavelets apresentam desempenhos similares aos dos baseados em FFT, para os modelos de canal simulados, com a vantagem adicional de não utilizarem prefixo cíclico, o que promove um uso mais eficiente do espectro.

Thesis (M. A.) --University of Limpopo, 2021 / This is an exploratory study conducted to assess the effectiveness of the digital migration in South Africa. This study focused on two areas of domicile, which embarked on the process of migrating in Limpopo Province i.e. Shayandima Village in Thohoyandou and Rapotokwane Village in Bela-Bela. The theories that were used to guide the study were the diffusion of innovations theory, political economic theory and media policy theory. These theories were employed to assist in assessing the process, the effectiveness and the importance of Digital Migration. The results for this study are revealed that 85% of respondents asserted that digital broadcasting is very effective and easy to use compared to the analog broadcasting systems, as it shows clear pictures, quality sound and access to more television channels. This help television viewers to get quality television programs. It was interesting to note that respondents mentioned that they did not regret migrating from analog to digital broadcasting because of the benefits and impact that the Set Top Boxes Set (STB)s have on their televisions. The findings reveal that the STBs are effective and affordable and enable to watch more television channels. There is also a need for the Department of Communication and Digital Technologies to ensure that every household in South Africa migrates to digital broadcasting system

<p>DAB (Digital Audio Broadcasting) is the radio digital system developed as an european standard by the ETSI, EN 300 400, based on the Eureka-147 group works, to improve the performance of the analogue radio systems (AM and FM). The system is based on the OFDM technology which allows DAB to exploit the spectrum frequencies in a better way with a higher quality of sound for mobile receivers specially. The main part of the OFDM system is based on the FFT algorithms to spread the data flow over different orthogonal carriers. The simulation has been developed in Simulink^TMand Matlab^TMand the layout designed follows faithfully the standard for the transmission system. The simulation can be reloaded by the user with the information presented in this thesis. Thus, this work can be continued to complete the DAB whole system simulation. The results obtained running this simulation show the main DAB system characteristics.</p>

DAB (Digital Audio Broadcasting) is the radio digital system developed as an european standard by the ETSI, EN 300 400, based on the Eureka-147 group works, to improve the performance of the analogue radio systems (AM and FM). The system is based on the OFDM technology which allows DAB to exploit the spectrum frequencies in a better way with a higher quality of sound for mobile receivers specially. The main part of the OFDM system is based on the FFT algorithms to spread the data flow over different orthogonal carriers. The simulation has been developed in Simulink&lt;sup&gt;TM&lt;/sup&gt;and Matlab&lt;sup&gt;TM&lt;/sup&gt;and the layout designed follows faithfully the standard for the transmission system. The simulation can be reloaded by the user with the information presented in this thesis. Thus, this work can be continued to complete the DAB whole system simulation. The results obtained running this simulation show the main DAB system characteristics.