Digital Broadcasting Receiver Research Articles

Multi-Frequency Interference Detection and Mitigation Using Multiple Adaptive IIR Notch Filter with Lattice Structure

Radio Frequency Interferences (RFI), such as strong Continuous Wave Interferences (CWI), can influence the Quality of Service (QoS) of communications, increasing the Bit Error Rate (BER) and decreasing the Signal-to-Noise Ratio (SNR) in any wireless transmission, including in a Digital Video Broadcasting (DVB-S2) receiver. Therefore, this paper presents an algorithm for detecting and mitigating a Multi-tone Continuous Wave Interference (MCWI) using a Multiple Adaptive Notch Filter (MANF), based on the lattice form structure. The Adaptive Notch Filter (ANF) is constructed using the second-order IIR NF. The approach consists in developing a robust low-complexity algorithm for removing unknown MCWI. The MANF model is a multistage model, with each stage consisting of two ANFs: the adaptive IIR notch filter Hl(z) and the adaptive IIR notch filter HN(z), which can detect and mitigate CWI. In this model, the ANF is used for estimating the Jamming-to-Signal Ratio (JSR) and the frequency of the interference (w(0)) by using an LMS-based algorithm. The depth of the notch is then adjusted based on the estimation of the JSR. In contrast, the ANF HN(z) is used to mitigate the CW interference. Simulation results show that the proposed ANF is an effective method for eliminating/reducing the effects of MCWI, and yields better system performance than full suppression (kN=1) for low JSR values, and mostly the same performance for high JSR values. Moreover, the proposed can detect low and high JSR and track hopping frequency interference and provides better Bit error ratio (BER) performance compared to the case without an IIR notch filter.

Evaluation of Rainfall Estimation Derived From Commercial Interactive DVB Receivers Using Disdrometer, Rain Gauge, and Weather Radar

Accurate measurement and monitoring of precipitation is crucial for many applications, such as flood and drought risk assessment and management. Conventional meteorological devices for estimating precipitation (i.e., rain gauges, disdrometers, active and passive remote sensors, be they ground-based, spaceborne, or airborne) have their own strengths and weaknesses. The latter are often related to time and space resolution, coverage, and cost. In the last two decades, several studies have been carried out to exploit opportunistic signals of terrestrial microwave communication links to improve precipitation estimation capability. This study describes and evaluates a method to retrieve rainfall rate from the signal-to-noise ratio obtained from commercial interactive digital video broadcasting (DVB) receivers [referred as to smart low-noise blocks (smartLNBs)]. During a 1-year measurement campaign carried out in Tuscany (Italy) with purposely deployed instruments, the precipitation values estimated from a set of SmartLNBs were compared with measurements from co-located rain gauges and disdrometer. The normalized mean absolute error (NMAE) and root-mean-square error (RMSE) obtained comparing the total cumulative precipitation from a SmartLNB and a disdrometer are 48.8% and 7.46 mm, respectively. Encouraging results also come from comparing the total precipitation amounts as measured by the SmartLNBs and by the rain gauges, with values of NMAE (respectively, RMSE) ranging between 44% and 82% (respectively, 5.2 and 11.5 mm).

Analysis of Diameter Changes Effect on Radiation Element to Improve Characteristics of Fullwave Loop Antenna

The article explained about the analysis of effect changes the diameter of radiating elements to the improvement of antenna characteristics. The antenna radiating element studied was solid copper wire and the type of antenna observed was an antenna that had a circular contour called the Full Wave Loop antenna. This antenna is use for digital television broadcast receiver applications and has a circle radius of 16 cm. Improved antenna characteristics were analyze for 3 types of radiation element diameter, namely; 3.5 mm; 2.5 mm and 2.0 mm. The Antennas were operated in a working frequency of 586 MHz, which is for digital television receiver broadcast channels. Based on the test data on the 3 diameter antenna elements and calculation analysis, it is known that the improvement is characteristics VWSR occurs in the radiation element with 2.0 mm diameter, the VSWR value is 1.93, return loss is 7.6 dB, antenna impedance is 97 Ω, gain of 12.88 dBi and antenna bandwidth of 7,17% and gain of 12.86 dBi, while the antenna characteristics of the radiating elements that are 2.5 mm and 3.5 mm larger are worse, among others; for VSWR 2.7 and 3.63. Return loss is -6,9 dB and 4.9 dB.Antenna impedance was 135 Ω and 175 Ω. The antenna gain was 8.78 dBi and 7.1 dBi. The smaller the diameter of the radiating element in the Full Wave Loop antenna will improve the characteristics of VSWR, Return loss, input impedance, gain. On the other hand, the smaller the radiation element will reduce the antenna bandwidth, so it is necessary to look for other methods to improve bandwidth capacity without changing the four characteristics of the good antenna. Likewise, the equation for determining the physical size of the radiating element is redefined.

18-2 視覚障害者向けデジタル放送受信機の開発(第18部門[テーマ講演]人にやさしい情報メディア技術)

18-2 視覚障害者向けデジタル放送受信機の開発(第18部門[テーマ講演]人にやさしい情報メディア技術)

ISDB-T 기반의 FULL-SEG 방송 수신 장치 개발

ISDB-T 기반의 FULL-SEG 방송 수신 장치 개발

5-7 デジタル放送受信機

5-7 デジタル放送受信機

디지털방송 단말의 HTML5 기반 웹 애플리케이션 실행 플랫폼

디지털기술의 발전으로 방송과 통신 영역 간에 융합이 이루어지면서 소비자의 다양한 디바이스를 통한 서비스(애플리케이션) 이용에 공간적, 시간적 제약을 제거하는 노력이 진행되고 있다. 특히 애플리케이션의 공통 실행 플랫폼으로 웹 (Web)의 중요성이 대두되면서 N-스크린 개념에 중요한 위치를 차지하고 있는 디지털방송 단말도 기존 데이터 서비스의 표준으로 삼고 있던 자바 (Java) 애플리케이션뿐만 아니라 웹 애플리케이션을 실행할 수 있는 플랫폼으로 발전하도록 요구되고 있다. 본 논문에서 소개하는 디지털방송 단말의 웹 애플리케이션 실행 플랫폼은 HTML5를 기반의 웹 애플리케이션 실행 엔진인 웹 커널과 웹 애플리케이션의 관리를 위한 윈도우 운영체제의 바탕화면 관리자와 유사한 웹 데스크탑, 그리고 웹 애플리케이션 개발자를 위한 SDK를 제공한다. 특히, 웹과 TV 영역의 기술적 접목을 통해 HTML5 기반 웹 애플리케이션이 프로그램 편성정보와 같은 방송 부가정보와 디지털방송 단말의 자원을 자유롭게 활용할 수 있는 웹 애플리케이션 개발 프레임워크를 제공한다. Due to the development of the digital technology, the territories of broadcasting and telecommunications are being converged and there have been the efforts to eliminate the spatial and/or temporal restrictions in utilizing the services (usually implemented as applications) via various devices (e.g. smart-phone, smart TV, pad-computer, etc). In the circumstances, Web is coming to the fore as a common running platform of the services and the digital broadcasting receivers are pressed to run Web applications as well as Java applications, which are the standard of data service of the digital broadcasting. The paper introduces a platform for running HTML5-based Web applications, which is equipped with a Web kernel (an engine for running HTML5 Web applications), a Web desktop (the facilities (with an UI similar to Window OS) for managing Web applications), and SDK (a set of API's for Web application developers).

Design of 3780 Points FFT Processor for DTMB Receiver

In this paper, a design of FFT processor for Digital terrestrial multimedia/television broadcasting (DTMB) receiver is presented. This processor is based on mixed-radix algorithms, prime factor algorithms and Winograd Fourier Transform algorithm (WFTA). Due to the adopted in-place algorithm in this design, the area consumption of the processor is reduced, and the simulation shows that SQNR of the processor is 60.5dB on the condition that the input and output data are both 13 bits.

A Study on Performance Improvement to Use Dummy Elements on A Monopole Array-assisted Doppler Spread Compensator for A Digital Terrestrial Television Broadcasting Receiver

This paper proposes an array antenna assisted Doppler spread compensator with dummy elements which are placed on either end of a monopole array for a digital terrestrial television broadcasting (DTTB) receiver. An array antenna assisted Doppler spread compensator, proposed previously, has a major drawback in performance degradation owing to mutual coupling effect among array elements. In order to solve the mutual coupling problem, dummy elements, placed on both sides of the monopole array mitigate performance degradation of a Doppler spread compensator arising from the mutual coupling among monopole array elements. Computer simulation results show that the dummy elements can reduce this performance degradation as well as expand the operating bandwidth of a Doppler spread compensator.

Moving Around Seoul

This article is a critical reflection on the author’s perambulatory experiences in Seoul as he follows the curves and strokes of contemporary Seoul’s streets. In theories of mobile communication technologies, there are few discussions about how and why people move and what happens during those movements. As the author manages his presence in the metropolitan environment of Seoul, he focuses on the new connections of social space and mobile communication technologies such as mobile phones, laptops, digital multimedia broadcasting (DMB) receivers, and GPS (global positioning system) navigation. By concentrating on corporeal and incorporeal motions via walking, driving, and riding public transportation, the author discusses how the usage of new mobile communication technologies reshapes urban movement and private and public, inside and outside, near and far, and here and there conceptions of social space.

Coarse time synchronisation for DVB-T2

A new coarse time synchronisation algorithm for second generation terrestrial digital video broadcasting (DVB-T2) receivers is presented. The proposed method provides not only an accurate coarse timing estimate but also a fast detection of DVB-T2 signals with slightly better robustness than the scheme presented in the DVB-T2 implementation guidelines.

70 dB Dynamic Range CMOS Wideband Digital Variable Gain Amplifier for AGC in DVB-T/H Receivers

This paper presents a novel variable gain amplifier (VGA) design which is applied in the automatic gain control loop of digital video broadcasting (DVB) receivers designed for standards DVB-T/H. The VGA is composed of three cascaded tunable gain stages to provide a 70 dB dynamic range with 2 dB gain steps. Each gain stage is based on a digital variable gain amplifier (DVGA) which is composed of a plurality of gain blocks (GBs) and a fully differential degeneration amplifier (FDDA). The GBs of the DVGA are digitally controlled current mirrors. A common-mode feedback circuitry is used to stabilize the FDDA by providing a stable common-mode voltage. Physical measurements on silicon show that the gain error is merely 0.55 dB given a 70 dB tuning range.

Low Cost SoC Design of H.264/AVC Decoder for Handheld Video Player

We propose a low cost and stand-alone platform-based SoC for H.264/AVC decoder, whose target is practical mobile applications such as a handheld video player. Both low cost and stand-alone solutions are particularly emphasized. The SoC, consisting of RISC core and decoder core, has advantages in terms of flexibility, testability and various I/O interfaces. For decoder core design, the proposed H.264/AVC coprocessor in the SoC employs a new block pipelining scheme instead of a conventional macroblock or a hybrid one, which greatly contribute to reducing drastically the size of the core and its pipelining buffer. In addition, the decoder schedule is optimized to block level which is easy to be programmed. Actually, the core size is reduced to 138 KGate with 3.5 kbyte memory. In our practical development, a single external SDRAM is sufficient for both reference frame buffer and display buffer. Various peripheral interfaces such as a compact flash, a digital broadcast receiver and a LCD driver are also provided on a chip.

Detection of Hierarchically-Modulated Data for Advanced T-DMB Receivers

This paper proposes an efficient detection method of hierarchically-modulated data for an advanced terrestrial digital multimedia broadcasting (AT-DMB) receiver. Hierarchical modulation, where low-priority (LP) symbols are hierarchically added to the existing high-priority (HP) symbols, has been considered to be useful for increasing the data rate in AT-DMB systems. The distance between two neighboring LP symbols is limited by the noise margin of HP symbols and thus should be shortened to minimize the effect on the detection of HP symbols. To cope with the poor condition of LP symbols, we introduce a coherent detection method based on coded decision-directed (CDD) channel estimation (CE). CDD-CE may provide an accurate estimation result even under the infrequent pilot arrangement of the T-DMB system. Additionally, we propose a moving average (MA) method in frequency direction to reduce noise existing in the estimated channel coefficients. Simulation results show that the proposed method can be a good solution to successfully detect LP data.

Advanced Conditional Access System for Digital Broadcasting Receivers Using Metadata

This paper presents an advanced conditional access system (CAS) for digital broadcasting receivers using program-related information called metadata. Digital broadcasting receivers using metadata (DBRM) provide services enhanced by using metadata and content stored in receivers, but it is so easy to edit stored content by using metadata that broadcasters require a content usage control mechanism for DBRM. The advanced CAS provides a secure environment for content and metadata in digital broadcasting receivers by preventing tampering and ensuring that only metadata certified by the broadcaster can be used. To evaluate the advanced CAS, we also developed a smart card and a prototype receiver on a PC. We have demonstrated in an implementation experiment that the advanced CAS can be implemented securely and utilized in broadcasting services using DBRM.

On Pilot-Symbol-Assisted Carrier Synchronization for DVB-S2 Systems

We consider the problem of carrier synchronization in future 2nd-generation satellite digital video broadcasting (DVB-S2) receivers. In this scenario, this task is made harder by the complexity constraints, related to the use of consumer-grade equipment. Making use of the distributed pilot symbols of the DVB-S2 standard, low-complexity techniques for fine frequency estimation and for detection in the presence of a strong phase noise, typical of consumer-grade equipment, will be proposed. The performance of the described algorithms will be analysed in detail through computer simulations.

Evaluation of a prototype remote control for digital broadcasting receivers by using semantic differential method

We prototyped an easy-to-use remote control for digital broadcasting receivers based on the result of usability tests that we made. In order to evaluate the prototype remote, we conducted experiments by using the semantic differential method. Two major components - functionality and appearance were extracted from the results of the principal component analysis. We found that there were significant differences in the each component score between the prototype remote control and a conventional one that had many buttons. The results indicate the effectiveness of our design methodology to develop an easy-to-use user interface.

S-band dual-path dual-polarized antenna system for satellite digital audio radio service (SDARS) application

This paper presents a novel compact dual-polarized antenna system for S-band satellite digital broadcasting receivers. The demonstrated antenna system consists of a low form factor dual-polarized antenna pair and two-stage low-noise amplifiers (LNAs) integrated with each antenna. One antenna is a low-profile annular ring patch antenna having a 90/spl deg/ phase-delay element for circular polarization (CP) and the other antenna is a reactively-loaded monopole antenna for linear polarization (LP). Both antennas operate in the same frequency range, from 2.320 to 2.345 GHz, while providing different polarizations to take advantage of the polarization diversity. Switches are used to select the mode (polarization) of operation. This ensures that appropriate dc bias is supplied to the operating LNA to process the received signal while no power is consumed by the idle LNA. The measured gains of the antenna system are 31.3 and 21.9 dBi for the CP and LP modes, respectively.

An array antenna assisted digital terrestrial television broadcasting receiver with vehicle speed estimation and Doppler spread compensation

AbstractFor digital terrestrial broadcasting, OFDM (Orthogonal Frequency Division Multiplexing) is used as the transmission system. While OFDM is robust to frequency‐selective fading due to delayed waves in a multipath environment, it is not resistant to Doppler spread for reception during movement. When the digital terrestrial broadcast is received while a vehicle is in motion, this weakness is a serious problem. The present authors have proposed a method for correcting Doppler spread by effectively canceling the motion of the moving body based on an array antenna to estimate the received signal at a point stationary to the ground. In the present paper, an algorithm is developed for estimating, from the received signal, the speed of movement of the vehicle, which was considered known in the previous method. A digital terrestrial broadcasting receiver is proposed for compensating the Doppler spread by estimating the speed of movement of the vehicle. By computer simulation, it is shown that the proposed algorithm can accurately estimate the speed of movement and that the bit error rate of reception of digital terrestrial broadcasts while in motion can be significantly improved. © 2006 Wiley Periodicals, Inc. Electron Comm Jpn Pt 1, 89(11): 46–55, 2006; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/ecja.20260

An advanced multimedia processing LSI suitable for HDTV applications

We have newly developed a multimedia processing LSI, targeting HDTV applications such as a digital broadcasting receiver based on ATSC or ARIB standards. It integrates many essential features such as multiple HDTV/SDTV input and output ports, an MPEG2-I/JPEG decoder, programmable video scaling engines, alpha-blending and a 2-D graphic engine. The chip can also achieve a multi-image display function by combining the elementary functions discussed. This LSI will be very useful in a broad range of multimedia applications such as DTV/ATV receivers, set top boxes, interactive TVs, cables and satellites.