Digital Terrestrial Broadcasting System Research Articles

A Deep Learning-Based Emergency Alert Wake-Up Signal Detection Method for the UHD Broadcasting System.

With the increasing frequency and severity of disasters and accidents, there is a growing need for efficient emergency alert systems. The ultra-high definition (UHD) broadcasting service based on Advanced Television Systems Committee (ATSC) 3.0, a leading terrestrial digital broadcasting system, offers such capabilities, including a wake-up function for minimizing damage through early alerts. In case of a disaster situation, the emergency alert wake-up signal is transmitted, allowing UHD TVs to be activated, enabling individuals to receive emergency alerts and access emergency broadcasting content. However, conventional methods for detecting the bootstrap signal, essential for this function, typically require an ATSC 3.0 demodulator. In this paper, we propose a novel deep learning-based method capable of detecting an emergency wake-up signal without the need for an ATSC 3.0. The proposed method leverages deep learning techniques, specifically a deep neural network (DNN) structure for bootstrap detection and a convolutional neural network (CNN) structure for wake-up signal demodulation and to detect the bootstrap and 2 bit emergency alert wake-up signal. Specifically, our method eliminates the need for Fast Fourier Transform (FFT), frequency synchronization, and interleaving processes typically required by a demodulator. By applying a deep learning in the time domain, we simplify the detection process, allowing for the detection of an emergency alert signal without the full suite of demodulator components required for ATSC 3.0. Furthermore, we have verified the performance of the deep learning-based method using ATSC 3.0-based RF signals and a commercial Software-Defined Radio (SDR) platform in a real environment.

Evaluation of the Field-Test Results of Advanced ISDB-T System With Low-Rate LDPC Codes

This article analyses low-density parity-check (LDPC) codes for forward error correction (FEC) in the next generation of digital terrestrial broadcasting systems for transmitting high-volume content services, such as ultra high definition television (UHDTV). We assess the performance of the LDPC codes used by the Advanced ISDB-T system with 2x2 MIMO transmission using experimental data obtained in field measurements in Brazil. Channel power, carrier-to-noise threshold, and receiving threshold were measured for four different low-rates LDPC codes, two modulation types, and three receiving antenna heights at outdoor sites in urban areas. The coverage analysis shows that the channel power presents a similar distribution for horizontal and vertical polarized signals. C/N threshold analysis shows that in sites with high vehicular traffic, the C/N threshold and reception threshold values were much higher than in other sites with less heavy vehicular traffic. Among the five coding-modulation combinations used in the field tests, the transmission configuration with LDPC code rate 2/16 and QPSK modulation was the one that presented the best results partially meeting the requirement of C/N <inline-formula xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink"> <tex-math notation="LaTeX">$\leq $</tex-math> </inline-formula> 0dB. The transmission configuration with LDPC code rate 3/16 and QPSK modulation showed C/N results just above 0dB, but offering 50% higher data transmission rate.

Selection and Justification of a Digital System Broadcasting for the Republic of Angola

In this work we seek to approach the choice of the Republic of Angola for the ISDB-T telebroadcasting system. The experimental results of the ISDB-T digital transmission system in the Republic of Angola are Execelente. Currently, the Japanese terrestrial digital broadcasting system (ISDB-T) is used in 14 countries around the world (Argentina, Bolivia, Brazil, Chile, Costa Rica, Japan, Peru, Paraguay, El Salvador, Uruguay, Honduras, Venezuela, Philippines, Botswana) and 6 more countries (Angola, Maldives, Sri Lanka, Guatemala, Ecuador, Nicaragua) have adopted this system. The study shows that ISDB-T is a system applicable in our country, as even with the transmitter operating at 50% of its maximum power, the signal is received in a large part of the city of Luanda, with failures only in regions far from the center urban. The implementation of a fully digital transmitter that is foreseen, the increase of the transmitter's power, among other changes, may provide better advantages in implementing the ISDBT in the Republic of Angola. The commitment comes at a time when Angola plans to cover the entire national territory, starting in 2023.

DASH Live Broadcast Traffic Model: A Time-Bound Delay Model for IP-Based Digital Terrestrial Broadcasting Systems

This paper proposes a live broadcast traffic model for an internet protocol (IP)-based terrestrial digital broadcasting system to transmit dynamic adaptive streaming over hypertext transfer protocol (DASH) media. The IP-based terrestrial digital broadcasting systems such as Advanced Television Systems Committee (ATSC) 3.0 transmit media content (e.g., full high definition and ultra-high definition) in units of DASH segment files. Although the DASH segment file has the same quality and playback time, the size of each DASH segment file can vary according to the media composition. The transmission resource of the terrestrial broadcasting system has increased the transmission capacity of broadcasting with new technologies. However, the transmission capacity is still limited and fixed compared to wired broadcasting networks. Therefore, a problem occurs with the efficiency of broadcasting resources and transmission delay when transmitting a variable segment file to a terrestrial digital broadcasting network. In this paper, the resource efficiency and transmission delay results that occur when transmitting the actual DASH segment file are simulated through the live broadcast traffic model, and the maximum delay time that a viewer accessing the terrestrial broadcast can experience is presented.

Backward Compatible Low-Complexity Demapping Algorithms for Two-Dimensional Non-Uniform Constellations in ATSC 3.0

Non-uniform constellation (NUC) is an advanced technology in digital terrestrial television broadcasting (DTTB) systems to reduce the shapping gap of BICM capacity to Shannon theoretical limit and provide performance gain. Two-dimensional NUC (2D-NUC) is a kind of NUC providing more gain but bringing higher demapping complexity at the receiver, which hinders its application prospects, especially in power limited systems. This paper proposes three novel demapping algorithms with reduced complexity for low to medium code rate 2D-NUCs in Advanced Television Systems Committee 3rd Generation (ATSC 3.0) standard. The proposed algorithms are based on the introduction of virtual points, the strategy of condensed symbols reduction and some reasonable approximations. There is a trade-off between the demapping complexity and performance. These three algorithms have different degrees of reduction in complexity and performance degradation, so they accommodate for different practical requirements. Theoretical analysis and simulation results are also given in this paper to prove the efficiency of the proposed demapping algorithms with reduced complexity.

Selective Mapping for Robust Data Transmission Using TxID Signal

For Advanced Television Systems Committee (ATSC) digital terrestrial broadcasting systems, a transmitter identification (TxID) technique is introduced to analyze interference among broadcasting transmitters in single frequency networks (SFN). Based on the TxID analysis results, the transmit power and emission time delay of each broadcasting transmitter can be adjusted to minimize the effects of co- and adjacent- channel interference. For this reason, TxID has been recognized as an important feature in SFN configurations for ATSC 1.0 and 3.0 standards. Recently, there has been increasing interest in employing TxID for data transmission. This paper proposes a TxID based data transmission method for use with ATSC 1.0 and 3.0 standards. The major advantage of this data transmission method is its robustness while maintaining TxID properties. Simulations and laboratory tests demonstrate that the proposed technique can achieve a robust data transmission with backward compatibility to legacy ATSC 1.0 and 3.0 receivers.

2-10 サーバ仮想化技術を用いた地上デジタル放送設備への取り組み(第2部門 放送現業)

2-10 サーバ仮想化技術を用いた地上デジタル放送設備への取り組み(第2部門 放送現業)

A scheme of AR-based personalized interactive broadcasting service in terrestrial digital broadcasting system

This paper proposes a AR-based personalized interactive broadcasting system via broadcast and broadband networks in terrestrial digital broadcasting system (DTV) environment. Augmented reality (AR) technology is a kind of mixed reality which 2D/3D graphics are integrated into the real world in order to enhance user experience and enrich information. A goal of AR-based interactive broadcasting system is to enable broadcasting program using AR technology to blend augmented content (2D/3D graphic object) with broadcasting content in real-time on receiving terminals. The proposed service scheme enables viewer-selectable augmented broadcasting service being provided from two content providers with authorization by a broadcaster and we show the implemented results under DTV environment.

Improved Polarized 2x2 MIMO Spatial Multiplexing Method for DVB-NGH System

Recently terrestrial digital broadcasting systems have experienced a growth with the demand of high-data rate. In order to meet such demand, the multiple-input multiple-output (MIMO) technology has received wide attention. This paper proposes a pre-coding method, which provides high-space channel correlation for the improved performance over terrestrial broadcasting channels when the MIMO spatial multiplexing (SM) is adopted for digital video broadcasting-next generation handheld systems. When signals with two different modulation orders are transmitted through two antennas, a method that is based on non-uniform power is also proposed for improved reception performance. To optimize the proposed method, phase shifting values for the pre-coding method and appropriate non-uniform power ratio are obtained. These obtained parameters are applied to a terrestrial broadcasting system, and then the performance improvement over the conventional SM is shown through computer simulations.

DVB-NGH 시스템을 위한 향상된 편파 2˟2 MIMO SM 기법 연구

Recently terrestrial digital broadcasting systems have experienced a growth with the demand of high data rate. In order to meet such demand, the MIMO technology has received a wide attention. This paper proposes a pre-coding method, which provides high space channel correlation for the improved performance over terrestrial broadcasting channels when the polarized MIMO SM is adopted for DVB-NGH systems. When signals with two different modulation orders are transmitted through two antennas, a method that is based on non-uniform power is also proposed for improved reception performance. To optimize the proposed method, phase shifting values for the pre-coding method and appropriate unequal power ratio are obtained. These obtained parameters are applied to a terrestrial broadcasting system, and then the performance improvement over the conventional SM is shown through computer simulations.

11-7 仮想化技術を用いた地上デジタルデータ放送設備への取り組み : サーバ機器への対応(第11部門放送現業&放送通信連携技術)

11-7 仮想化技術を用いた地上デジタルデータ放送設備への取り組み : サーバ機器への対応(第11部門放送現業&放送通信連携技術)

Field estimation for terrestrial digital broadcasting in Western part of Fukuoka

Fukuoka tower plays an important role as main stations for several terrestrial digital broadcasting systems in Fukuoka area, which are going to completely replace the conventional analogue broadcasting systems in 2011. The input power of the digital broadcasting system is reduced about one-tenth of the old analogue system, but the new system needs many relay stations to maintain high quality of services. In this paper, focusing on two relay stations in the Western part of Fukuoka, we estimate the field distributions with respect to both the main and a relay station by using the discrete ray tracing method (DRTM). We also discuss the necessity of a relay station in conjunction with the blind zones of the main station due to shadowing in a mountainous area.

Robust timing recovery for TDS-OFDM-based digital television terrestrial broadcast systems

As an effective technique for combating multipath fading and for high-bit-rate transmission over wireless channels, orthogonal frequency-division multiplexing (OFDM) is extensively used in modern digital television terrestrial broadcasting (DTTB) systems to support high performance bandwidth-efficient multimedia services. In this paper, a new robust timing recovery scheme is proposed for the time domain synchronous OFDM (TDS-OFDM) based DTTB systems. Simulations under different channel situations verify the efficiency of the proposed scheme

A 63-mW H.264/MPEG-4 Audio/Visual Codec LSI With Module-Wise Dynamic Voltage/Frequency Scaling

A single-chip H.264 and MPEG-4 audio-visual LSI for mobile applications including terrestrial digital broadcasting system (ISDB-T / DVB-H) with a module-wise, dynamic voltage/frequency scaling architecture is presented for the first time. This LSI can keep operating even during the voltage/frequency transition, so there is no performance overhead. It is realized through a dynamic deskewing system and an on-chip voltage regulator with slew rate control. By the combination with traditional low power techniques such as embedded DRAM and clock gating, it consumes only 63 mW in decoding QVGA H.264 video at 15 frames/sec and MPEG-4 AAC LC audio simultaneously.

Transmission System for ISDB-T

The Association of Radio Industries and Businesses in Japan decided the specifications for a digital terrestrial broadcasting system called ISDB-T in 1998. The ISDB-T transmission system is recommended in ITU-R Recommendation BT.1306. Planning criteria of the ISDB-T system are recommended in ITU-R Recommendation BT.1368. This paper describes the transmission scheme of the ISDB-T system. First, it explains features of the ISDB-T system. Second, it describes transmission systems such as modulation, error correction, orthogonal frequency division multiplexing framing, transmission and multiplexing configuration control, guard interval, etc. Finally, it concludes discussion of the ISDB-T transmission system and describes transmission parameters used in Japan.

地上デジタル放送用適応型回り込みキャンセラの基本検討

A loop canceller is described for coping with loop coupling at relay stations for OFDM (orthogonal frequency division multiplexing) SFNs (single frequency networks) in terrestrial digital broadcasting systems. An iteratively adaptive algorithm based on the least means square method is used for the loop cancellation filter. Use of this adaptive filter reduces hardware complexity and minimizes hardware size. Computer simulation showed that the proposed canceller is effective for loop cancellation in actual OFDM digital broadcasting systems.

周波数領域処理を用いた地上デジタル放送用逐次適応型回り込みキャンセラ

Frequency domain adaptive filters, both orthogonal transform and subband types, are introduced into loop cancellers, which were developed to cope with loop coupling and multipath distortion at relay stations in digital terrestrial broadcasting systems using OFDM (Orthogonal Frequency Division Multiplexing). An additional loop configuration and a coefficient duplicating method are also proposed and evaluated for subband-type cancellers. Computer simulation showed that frequency-domain processing has better performance than transversal-type processing.

デジタル放送・伝送方式 ＩＦ帯で動作する逐次適応フィルタを用いたＯＦＤＭ用中継装置

Several cancelers have been developed for coping with multipath arid loop coupling at relay stations in ISDBT digital terrestrial broadcasting systems using OFDM (Orthogonal Frequency Division Multiplexing) signals, This paper describes simplified iteratively adaptive algorithms based on a least means square method for cancellation filters, The use of an adaptive filter operating in IF bands greatly simplifies the required hardware, minimizes its size, and does not degrade the system performace. The results of a computer simulation showed that the algorithms can be used in OFDM digital broadcasting systems.

12-8 地上デジタル放送用STL/TTL装置開発と主要性能

12-8 地上デジタル放送用STL/TTL装置開発と主要性能

A Proposal of CDM System based on OFDM for Simultaneous Common and Local Areas Terrestrial Broadcasting.

In this paper, CDM is applied to the digital terrestrial broadcasting system based on OFDM. This proposed system could provide both common and local area services by using CDM for local broadcasting. Proposed system can be easily adapted to OFDM digital terrestrial broadcasting system, which proposed by Japanese BST-OFDM ISDB-T, by adding only one spread spectrum block. Moreover, we will get advantages from this adaptation, such as spectrum efficiency, simultaneous common and local area broadcasting. Performance of proposed system is shown that high data rates can be served. Its performance is better than FDM system and better performance can be reached by using sectorization and Walsh codes in proposed system. From results, different multimedia services can be supported by the proposed system that applied in different bandwidths.