Real Time Traffic Information Service Using Terrestrial Digital Multimedia Broadcasting System

The major contribution of this paper is the implementation of real time traffic and traveler information service through the terrestrial digital multimedia broadcasting (T-DMB) system, which are known to be suitable for the mobile data services as well as audio and video services. The implemented system converts the Korean characteristic traffic information into the transport protocol expert group (TPEG) messages, and provides them to the T-DMB system. By testing the service with the TPEG message decoder implemented in the navigation system on PDA and laptop, it has turned out that it can be used as a highly efficient traffic information service system that could be adopted in Korea as well as in European countries     

Novel Equalization On‐Channel Repeater with Feedback Interference Canceller in Terrestrial Digital Multimedia Broadcasting System

In this paper, we propose a novel equalization on‐channel repeater (OCR) with a feedback interference canceller (FIC) to relay terrestrial digital multimedia broadcasting signals in single frequency networks. The proposed OCR not only has high output power by cancelling the feedback signals caused by insufficient antenna isolation through the FIC, but also shows better output signal quality than the conventional OCR by removing multipath signals existing between the main transmitter and the OCR through an equalizer. In addition, computer simulations and laboratory test results demonstrate that the proposed OCR successfully cancels feedback signals and compensates channel distortions and provides a higher quality transmitting signal with higher output power than conventional OCRs.     

浅述基于TDS-OFDM技术的数字电视传输系统

本文简单介绍了DMB-T传输系统的调制模式,以及DMB-T所采用的主要技术和系统特点。     

地面数字电视信号与GPS相结合的定位系统

为了解决在城市楼宇间可见GPS卫星常常不足4颗而导致无法定位的问题,通过使用地面数字电视信号,实现了这种恶劣环境下的成功定位.而当GPS卫星数大干4颗时,利用数字地面电视信号可以改善GDOP,提高定位精度.介绍了系统的工作原理,通过计算机软件仿真实现了地面数字电视信号的模拟及单点和多点的移动定位,结果表明通过地面数字电视和GPS结合的定位系统可以提高定位精度,解决CPS卫星不足的问题.     

地面数字多媒体广播标准T-DMB

介绍了地面数字多媒体广播标准T-DMB的背景、系统结构与技术特点，并对其相关地面数字移动电视传输技术和业务模式进行了讨论.     

Equalization On-Channel Repeater for Terrestrial Digital Multimedia Broadcasting System

This paper presents technical requirements of on-channel repeaters (OCRs) to broadcast the terrestrial digital multimedia broadcasting (T-DMB) signals in single frequency network (SFN) environment. In order to meet such requirements, the configuration and implementation method of the equalization OCR are proposed. The proposed equalization OCR does not have only short processing delay, but also provides high quality transmitting signals with high power because of the rejection capability of a feedback signal introduced by incomplete antenna isolation and multipath signals existing between a main transmitter and the OCR. Computer simulations and laboratory tests results are provided to figure out performance of the proposed equalization OCR.      

浅析地面无线数字电视广播系统建设

地面无线数字电视发展迅速,特别是随着国标的出台,地面无线数字电视的发展将迎来新一轮快速发展的时代.发展地面无线数字电视,是加速推进广播电视“村村通”工程的有效方式.首先概述了地面无线数字电视,然后介绍地面无线数字电视的优势,最后从建设需求、标准选择、系统结构和组成、信号覆盖情况等多方面,阐述新余市广播电视台的地面数字电视广播系统建设情况.     

数字电视地面广播系统信息解析算法

数字电视地面广播系统提供了多种传输模式,用以满足不同的业务和不同的组网环境对信号质量的要求,从而实现运营的灵活性和经济性,这些模式参数都通过系统信息来指示。准确地进行系统信息解析是系统终端实现正常接收的关键,提出了一种数字电视地面广播的系统信息解析算法。实验结果表明,该算法具有很高的可靠性,其与系统最低载噪比门限之间的裕度大于1 dB,可以有效保证系统终端的正常接收。     

关于地面数字电视广播传输标准的学习笔记

在学习美国和欧洲(还有日本)的地面数字电视广播(DTTB)传输标准的基础上,针对地面数字电视广播快速移动接收的需求,提出:1)与制订地面数字电视广播新传输标准有关,在系统层设计中合理地缩小数据结构,并合理地设计同步码/训练序列(PN码);2)在接收端的解调器中,采用某种"过取样的相位跟踪技术",以充分利用主信号(有或无)和强回波信号的能量,保证在复杂多径效应环境下容易实现可靠的移动接收.对于制订具有更多自主知识产权的中国地面数字电视广播的传输标准而言,上述两方面的重要措施只有在采用VSB,QAM或OQAM调制的单载波系统的时间域高速数字处理中才能够实现.而且,这种新的单载波系统在组成单频网(SFN)时,与任何多载波系统相比,其技术简单而不需要卫星GPS系统,因而造价低、容易实现和维护.     

Compact Dipole Antenna for Terrestrial Digital Multimedia Broadcasting Service

A compact dipole antenna for the terrestrial digital multimedia broadcasting (TDMB) application is presented. The length of the antenna is about 0.06λ at the TDMB resonance frequency of 190 MHz. Miniaturization of the antenna is achieved by using meander structures and lumped elements. The proposed antenna has two resonance frequencies and covers the TDMB band from 174 MHz to 216 MHz in Korea. The antenna has good impedance bandwidth and radiation characteristics for the TDMB. The experimental results of the designed dipole antenna are presented and analyzed.     

地面数字电视广播传输标准SMCC+系统的关键技术

描述了由电子科技大学提出的地面数字电视广播传输标准SMCC (Synchronized Multicarrier CDMA plus)系统。通过与现有的地面数字电视广播(Digital Television Terrestrial Broadcasting)标准在调制方式、同步、信道估计、相噪技术、峰平比、编码等方面的比较,证明了SMCC 系统具有比现有的标准更优越的性能。     

下一代地面数字电视广播系统关键技术

较全面地介绍了下一代中国地面数字电视广播系统的关键技术,其中包括改进的帧结构、发射分集、先进的信道编码和调制、多业务支持、广播回传信道和时频域定位等。仿真结果表明这些技术的应用使系统性能良好。     

评中国地面数字电视广播传输标准

依据昊奕彦等采用的"系统载噪比性能的公正比较"方法和样机测试结果说明:中国地面数字电视广播传输标准(C-std)优于ATSC或DVB-T.并建议对该标准增加一些可选项,以改进其性能.     

数字电视地面广播系统的截止率求解

针对现有5种数字电视地面广播系统(ATSC,DVB,ISDB,ADTB-T,DMB-T),给出了AWGN信道和多径衰落信道下各系统的截止率性能,并进行了比较.     

ATSC Terrestrial Digital Television Broadcasting Using Single Frequency Networks

In this paper, we propose an efficient method to broadcast digital television signals using single frequency networks (SFNs) within the Advanced Television Systems Committee (ATSC) transmission systems. In implementing the SFNs of an 8‐vestigial side band (8‐VSB) Digital Television (DTV) system, the ambiguity problem of the trellis coder is unavoidable in a conventional ATSC transmission system. We propose a memory initialization of the trellis coder to resolve this ambiguity problem. Since the proposed scheme to synchronize multiple transmitters minimizes the changes from the conventional ATSC system, the hardware complexity for these changes is very low. Our simulation results show that the proposed scheme makes a less than 0.1 dB degradation at the threshold of visibility with a bit error rate of 3×10^?6 in the additive white Gaussian noise (AWGN) channel. It is possible to reduce the performance degradation by increasing the initialization period of the proposed scheme.     

Transmission System for ISDB-T/sub SB/ (Digital Terrestrial Sound Broadcasting)

In the Integrated Services Digital Broadcasting-Terrestrial Sound Broadcasting (ISDB-T/sub SB/)transmission system, a narrow-band orthogonal frequency division multiplexing with one or three segment(s) is adopted. It is robust against multipath interferences in urban radio wave transmission. In addition, it is capable of mobile reception because of time interleaving. A transmission bandwidth of 432 kHz for one segment is narrow enough in order to allocate channels flexibly, and the "connected transmission" scheme, which allows multiple segment transmission with no guard band, is a highly efficient usage of the frequency resource. The ISDB-T/sub SB/ transmission system is consistent with ISDB-T, hence it enables a common receiver for partial reception of ISDB-T, digital television broadcasting. In this paper, the ISDB-T/sub SB/ transmission system,especially the differences from the ISDB-T transmission system, is introduced,and the current status of the ISBD-TSB digital terrestrial sound broadcasting service is shown.     

地面数字多媒体/电视传输标准方案的进展

DMB—T标准方案历经了方案论证、系统仿真、样机研究、IC流片和产品机顶盒样机开发等多个研发阶段。经过多种形式的测试、评估和试验及充分验证，其性能先进，产权清晰，技术成熟，满足基本需求，产业化准备就绪。     

地面数字电视广播单频网应用实践

对地面数字电视传输标准的单频网性能进行了分析,并结合地面数字电视单频网的实际测试结果,提出地面数字电视单频网覆盖中的若干建议.