Digital switch-over: possible propagation based solutions to the lack of spectrum

Currently digitalization of analog broadcasting systems is taking place because digital broadcasting has many advantages such as efficient use of the frequency spectrum and provision of high-quality content broadcast services. However, service start time in digital broadcasting systems is slower compared to the analog broadcasting systems. Therefore, digital broadcasting systems require fast and efficient synchronization methods. In this paper, we propose a fast frame detection technique without sampling frequency correction for the Digital Radio Mondiale (DRM) receiver and show the performance of the proposed method using computer simulations and implementation on hardware.

It is envisioned that all broadcasting systems will be digitalized in future. New services and more information require high data rates for broadcasting systems. There are many digital audio broadcasting standards in the world, such as DAB (Digital Audio Broadcasting) in Band III and Band L, DRM (Digital Radio Mondiale)and HD Radio in AM band and FM band. In this paper, we will present a general purpose SDR (Software Defined Radios) platform to realize digital audio broadcasting systems, including transmission and reception. In the platform, we not only can test novel digital technologies but also experiment with different service modes.

Advances in wireless communications have enabled various technologies for wireless digital communication. In the field of digital radio broadcasting, several specifications have been proposed, such as Eureka-147 and digital radio mondiale (DRM). These systems require a new spectrum assignment, which incurs heavy cost due to the depletion of the available spectrum. Therefore, the in-band on-channel (IBOC) system has been developed to work in the same band with the conventional analog radio and to provide digital broadcasting services. This paper discusses the function and algorithm of the high definition (HD) radio frequency modulation (FM) digital radio broadcasting system. Content includes data format allocation, constellation mapping, orthogonal frequency division multiplexing (OFDM) modulation of the transmitter, timing synchronization, OFDM demodulation, integer and fraction carrier frequency (integer carrier frequency offset (ICFO) and fractional CFO (FCFO)) estimation, and channel estimation of the receiver. When we implement this system to the field programmable gate array (FPGA) based on a hardware platform, both theoretical and practical aspects have been considered to accommodate the available hardware resources.

Digital radio mondiale (DRM) is the world's only standard-open digital radio system for short-wave, medium-wave/AM and long-wave radio broadcasting with the ability to use existing frequencies and bandwidth across the globe. Implementation of digital radio in today's AM bands (i.e. long, medium and shortwave) based on DRM will enable operators to provide services which will be successful with both existing and future high-quality services. DRM content server is important part of the DRM radio system. This paper gives a design solution of DRM content server's structure.

Background: It is a common fact that the rapid development of technology influenced many aspects of the world, including mass communication. Television, as the most popular and familiar broadcast media in Indonesia, has experienced several changes due to the presence of advanced technology. One of the significant transformations is the transition from analog to digital broadcasting systems. The new era of digital broadcasting could improve the performance and quality of digital television itself. Purpose: This recent study aimed to obtain an overview of the realization carried out by one of the local private broadcasting institutions in Banten, JPM TV. Methods: Using a qualitative case study along with in-depth interviews and observation as data collection techniques, this study examines JPM TV from various aspects in realizing digital TV broadcasts in Banten Province. Results: The study’s findings highlighted that JPM TV strives to realize digital broadcasting by gradually replacing equipment with tools that support digital broadcasting and elements of human resources trained and prepared with special internal and external training. JPM TV also collaborated with LPPM (Mix Broadcasting Organizing Agency), namely Mix Metro TV. The ongoing process is coordinated with the government. Obstacles faced during the migration process are the socioeconomic conditions of the people who have not been able to support the digital broadcasting process, which is characterized by the difficulty of obtaining digital broadcasting at relatively low prices; besides that, it is also necessary to increase the capacity of Human Resources (HR) so that television shows are more comfortable to watch. Implications: One of the implications is that the government must innovate to provide incentives that can stimulate the readiness of the digital broadcasting ecosystem.

This paper presents a compact structure of recursive discrete Fourier transform (RDFT) with prime factor (PF) and common factor (CF) algorithms to calculate variable-length DFT coefficients. Low-power optimizations in VLSI implementation are applied to the proposed RDFT design. In the algorithm, for 256-point DFT computation, the results show that the proposed method greatly reduces the number of multiplications/additions/computational cycles by 97.40/94.31/46.50% compared to a recent approach. In chip realization, the core size and chip size are, respectively, 0.84 × 0.84 and 1.38 × 1.38 mm2. The power consumption for the 288- and 256-point DFT computations are, respectively, 10.2 (or 0.1051) and 11.5 (or 0.1176) mW at 25 (or 0.273) MHz simulated by NanoSim. It would be more efficient and more suitable than previous works for DRM and DRM+ applications.

This thesis presents a green design of fast recursive discrete Fourier transform (RDFT) architecture. The advantages of the proposed design include high-throughput, power-efficient, memory-free and more reconfigurable. This thesis also discuss the issue of applying this RDFT design to Modified Discrete Cosine Transform (MDCT) and Inverse Modified Discrete Cosine Transform (IMDCT), which results in an improvement of hardware-sharing and achieves lower-cost. To improve the lack-of-efficiency problem in traditional RDFT architecture, the 2-D architecture algorithm is used in our design. Compared with the latest RDFT architecture proposed by Lai et al, 49.53% reduction of the overall clock cycles is presented in our design; and the computational amount of multiplication and addition presented are reduced to 53.60% and 53.03% of Lai’s design. In addition, the proposed architecture holds four times of DTPT (Data Throughput per Transformation, DTPT) than the traditional architecture; which achieves our goal of presenting a low complexity and low power-cost design. Furthermore, this architecture is applied on Digital Radio Mondiale (DRM) system in our design. Not only DFT computation(288、256、176、112 point) but MPGE-4 HE-AAC techniques are applied on DRM audio coding(1920、240 point). Therefore, to design a common architecture of DFT and IMDCT becomes an important issue for portable DRM receiver. This system is used to examine the performance of the RDFT architecture which we proposed in the front text as well as to discuss other architectures in this article. Moreover, this RDFT processor is implemented by using TSMC 0.18µm 1P6M CMOS technology. The core size is 0.84x0.84mm2 and the power consummation is 14.6mW@25MHz. To conclude, the proposed design would be more efficient and more suitable for DRM applications than previous works.

Modern radio-communications have begun the transition process from analog to digital radio-communications and broadcasting. During this transition process, main changes are required in exciter units of transmitters. The architecture of transmitters themselves is the same for both digital and analog broadcasting, but the exciters used for digital broadcasting have to create analog RF exciting signals for the transmitters from the digital data stream. The most common modulation procedure used in digital broadcasting systems is OFDM with QPSK or some kind of QAM keying of sub carriers. Apart from RF signal generation, the exciters are often responsible for control of the whole system, because control data is often included in the digital stream distributed from the broadcast center to the transmitters

From home entertainment we know a number of digital entertainment sources which we cherish. Especially Digital Broadcasting, such as DAB, DVB, HD-Radio and SDARS just to name a few, are entering the automotive market. Premium car manufacturers are offering DAB, DVB-T as well as HD-Radio and SDARS as digital sound broadcasting for their customers. However, a lot of efforts need to be undertaken to get good performance. This paper deals with answering the often asked question, why digital broadcasting systems in vehicular environments do not perform as good as their theoretical performance should intend. With an excessive measurement campaign with a number of premium car manufacturers in Germany, we found three main arguments; a) the digital modulation becomes week in terms of bit-errors with enhanced data rates b) wideband modulation schemes, such as COFDM for example, are fragile in fading environments, especially reactive on frequency selective fading and c) used coding and modulation techniques can cope with single-frequency and single-event interferences well but not with permanent broadband interference, which are often found in EMC signatures in well-equipped luxury cars.

The uniform content label (UCL) is one kind of information content metadata developed on the basis of URL (Uniform Resource Locator), which describes feature vector of information content in full range of multidimensional. The UCL technology is applicable to the markup of information content, mainly for the main audience in the media, Internet and related industries. This paper proposes a UCL label push method based on DRM (Digital Radio Mondiale) broadcasting. By using the data segmentation and fountain coding, the method can ensure the effectiveness of the UCL label push in the narrow-band broadcasting transmission condition of DRM.

A digital HF radio broadcasting network such as Digital Radio Mondiale (DRM) may be enhanced by constant monitoring of the quality of service (QoS) provided to its customers, the listening audience. For this purpose, a number of test receivers need to be distributed throughout the target broadcast region. The paper addresses the question of how many test receivers are required for this purpose, where they should be placed, and how to extrapolate the measurements they make over the broadcast service area or areas.

As an effective technique for combating multipath fading and for high-bit-rate transmission over wireless channels, orthogonal frequency division multiplexing is extensively used in modern digital television terrestrial broadcasting systems to support high performance bandwidth-efficient multimedia services. Accurate channel estimation is important for the application of simple channel equalization for the broadband multi-carrier orthogonal frequency division multiplexing systems and the accuracy of the channel estimation is crucial to the performance of the overall orthogonal frequency division multiplexing system in terms of the symbol error rate. In this paper, a robust channel estimation scheme is proposed for the receiver of the time domain synchronous orthogonal frequency division multiplexing based Chinese digital television terrestrial broadcasting systems. Simulations under different channel situations show that the proposed channel estimation scheme can also effectively solve the phase noise problem existing at the receiver and verify the efficiency of the proposed scheme.

지상파 TV의 디지털 전환이 완료되었지만 지상파 라디오는 전송방식을 결정하지 못해 아날로그 방송을 유지하며 표류하고 있는 상태이다. 본 연구에서는 지상파 방송사의 종사자를 대상으로 상호지향성 모델을 토대로 디지털 라디오 전송방식을 결정하는 중요 요인에 대한 인식차이를 살펴보고 쟁점 요인을 도출하였다. 연구결과, 지상파 방송 3사는 디지털 라디오가 점유할 주파수 대역 선택에서 가장 큰 인식의 차이가 있으며 제작과 송출의 병행 여부, 주파수 이용 효율성, 방송 품질과 서비스 정도는 서로 의견의 차이가 없는 것으로 나타났다. 그리고 디지털 라디오 방송의 전환에 있어 가장 큰 쟁점 요인은 FM 라디오방송이 사용하는 주파수대역(88-108 MHz)과 지상파 DMB방송 주파수대역(VHF Ch7~13), FM 라디오방송 인접대역(76~88MHz: VHF Ch5~6) 중 어떤 주파수 대역을 디지털 라디오용으로 선택하는지의 문제, 즉 DAB+, HD-Radio, DRM+ 가운데 특정 전송방식을 선택하는 문제로 귀결되었다. 이에 본 연구에서는 제작 송출 병행이 가능하고 송 중계소 1-2개로 송신 효율을 높일 수 있고 신규 사업자 진입이 가능한 방식을 채택함으로써 라디오방송서비스의 품질과 이용자의 만족도를 높일 것을 제안하고자 한다. Though the digital transition of terrestrial TV has been completed, the transmission system for terrestrial radio has not been determined and terrestrial radio still keeps its analog transmission. This study, under coorientation model, aims to explore the cognitive difference in recognizing important factors to be considered in deciding the digital radio transmission system between the employees of terrestrial broadcasters and then crucial issues related to the factors are driven. It has been found that the most big cognitive difference among the employees of three major terrestrial broadcasters lies in selecting frequency band for digital radio transmission. But there was little difference of opinion on simultaneous production-transmission, efficiency of frequency usage, broadcast quality and standards of service. The most disputable point in transition to digital radio broadcasting is selecting the frequency band for digital radio between the frequency bands used for FM radio broadcast (88-108MHz), terrestrial DMB (VHF Ch7~13) and FM radio adjacent broadcast band (76~88MHz: VHF Ch5~6). So, the question concludes into the selection issue between DAB+, HD-Radio, and DRM+. To improve the quality of radio broadcasting service and enhance the satisfaction of listeners, it is desirable to allow to operate both production system and transmission station, to enhance high transmission efficiency with minimum transmission facility, and to permit new entrance of broadcasters.

The 26 MHz band is the highest frequency broadcasting band covered by DRM bellow 30 MHz. Due to its low use for long-range transmissions, this band is been tested for using the DRM digital radio for local coverage. This paper shows the results for mobile reception of two field trials made in Mexico City and Brasilia.

Orthogonal frequency division multiplex-single frequency network (OFDM-SFN) has been widely used in the digital audio broadcasting system (DAB) and the terrestrial digital video broadcasting system (DVB-T) as a scheme of downlink broadcasting service. A novel system structure of single frequency cellular network (SFCN) is proposed by applying OFDM-SFN to conventional cellular systems. Transmitter macrodiversity and receiver selective diversity are adopted in the downlink and the uplink respectively. Theoretical analysis and numerical simulation in comparison with conventional cellular systems demonstrate the performance improvement of the proposed system.