T-DMB手机电视的硬件实现方案

概述了T-DMB系统,描述了该系统的传输机制,给出了手机电视接收端的基带硬件框图并分析了信号的处理流程,最后介绍了两款T-DMB基带处理芯片.     

T-DMB手机电视接收终端探讨

对T-DMB手机电视接收终端中广播电视接收处理系统的组成和原理作了介绍,并针对小型化、低功耗、和高性价比等难题,结合手机及其芯片设计的解决方案进行了探讨,对三星SPH-B2300机型进行了点评.另外,还对T-DMB接收终端的研发提出了建议.     

基于TMS320DM320的移动数字电视设计

介绍了基于T-DMB标准和TI数字多媒体芯片的移动数字电视的软、硬件设计理论和方法.仿真结果表明该方案功耗低,灵敏度高,可实时播放.     

T-DMB系统容量分析与节目划分方法研究

T-DMB系统在1.536MHz带宽上能提供的最大数据速率是运营商极为关注的问题.通过对T-DMB系统的帧结构和编码方案分析,给出了T-DMB的系统容量,在结合T-DMB试验网实测数据基础上,提出了T-DMB系统承载节目的划分方法.     

T-DMB条件接收系统带宽开销研究

条件接收系统是T-DMB手机电视加密控制的核心保证,为手机电视的运营提供了必要的技术手段。通过对T-DMB条件接收系统的具体实现方案的研究,分析了T-DMB条件接收系统的引入带来的额外带宽开销。     

地面数字多媒体广播(T-DMB)标准与应用

近年来,以移动电视、数字多媒体广播为代表的新兴媒体,逐渐成为技术和市场研究的重点.本文从系统组成、协议分层、组网试验以及标准化情况等诸方面,介绍分析了移动多媒体广播领域主流标准之一——T-DMB,并初步分析比较了T-DMB和DVB-H的技术特性.     

T-DMB技术及其应用

多媒体技术和移动通信技术的飞速发展激发了人们进行视频信息交流的需求。本文针对手机电视三大标准之一的T-DMB标准,介绍了T-DMB系统的历史和基本原理,进而阐述了T-DMB系统MUSICAM 信号源编码、COFDM信道编码调制、单频同步网等关键技术及其在上海的应用。     

T-DMB网络规划方法研究

在总结T-DMB试验网经验基础上结合该网络特点对T-DMB网络规划方法进行了研究,阐述了T-DMB链路预算方法,估算出各种传播环境下的覆盖半径,并结合网络利用规划仿真软件和试验网实际参数,对T—DMB网络的规划方法进行了描述。     

Envivio宣布推出电信级AVS编码器

3月31日，卓胜微电子（上海）有限公司召开新闻发布会，正式推出一款基于DAB／T-DMB标准的移动数字电视解调芯片MXD0120，是一款功耗低、尺寸小的移动数字电视解调芯片。公司首席执行官许志翰先生指出：“功耗和面积是移动设备最重视的关键指标，采用功耗低，面积小的芯片意味着移动设备可以更小巧，可连续观看更长时间的电视节目。     

T-DMB标准视音频编码容错技术研究

从视音频编码角度出发,对提高T-DMB系统视音频播放质量的一些客错技术进行了总结归纳.介绍了T-DMB标准视音频编码的基本原理,讨论了T-DMB系统固有的客错特性,对基于解码端客错工具的错误隐藏技术进行了总结.     

Design of the Channel Estimation Algorithm for Advanced Terrestrial DMB System

This paper describes a channel estimation algorithm for the advanced terrestrial digital multimedia broadcasting (T-DMB) transmission system which is fully backward compatible with the conventional T-DMB standard. The advanced T-DMB has enhanced features which provide higher transmission data rate for increasing program channel capacity and better multimedia A/V service quality than the conventional T-DMB system by adopting a hierarchical modulation and scalable audio/video CODEC. To support the higher data rate transmission for the advanced T-DMB, high performance channel estimation and equalization techniques should be adopted into the advanced T-DMB receivers. In this paper, we propose a new channel estimation technique for the Advanced T-DMB to compensate channel distortion under dynamic multipath environment.      

Remultiplexing Eureka-147 Ensemble With MPEG-2 TS for T-DMB Multimedia Service

This paper introduces a layered structure of the Korean terrestrial digital multimedia broadcasting (T-DMB) ensemble based on Eureka-147 and suggests a new transmission architecture for flexible T-DMB service. In the suggested transmission architecture, MPEG-2 transport stream (TS) for T-DMB multimedia service is inserted into the ensemble distributed via the ensemble transport interface (ETI). Thus, we propose a novel algorithm remultiplexing the ETI with MPEG-2 TS. The architecture of ETI remultiplexing algorithm is described as a four-step process, and implemented as real-time embedded software in an ETI remultiplexing system. The design and implementation of the interoperable ETI remultiplexing system available for a small-scale transmission system for T-DMB service is described in detail.     

SVC Application in Advanced T-DMB

Commercial terrestrial digital multimedia broadcasting (T-DMB) service was launched in the Republic of Korea. Reflecting recent demands of high quality video, Advanced T-DMB(AT-DMB) adopting a hierarchical modulation is being developed as the way to increase the payload data. Based on the AT-DMB system, this paper proposes a method to provide increased video quality with high spatial resolution. By using the emerging H.264/MPEG-4 AVC amendment 3 scalable extension (SVC), the proposed method is able to support high spatial resolution as well as the currently serviced spatial resolution while retaining the backward compatibility to T-DMB. In the experimental results, the benefits in terms of coding efficiency and spatial scalability are proven in comparison with the conventional T-DMB and alternative methods to provide a high spatial resolution video.      

DVB-T/H and T-DMB: Physical Layer Performance Comparison in Fast Mobile Channels

Terrestrial or Handheld Digital Video Broadcasting (DVB-T/H) and Terrestrial Digital Multimedia Broadcasting (T-DMB) are two popular broadcasting standards that enable digital television transmissions to handheld receivers. This paper presents a comprehensive performance comparison between the physical layers of DVB-T/H and T-DMB when employed for mobile communications. By exploiting a recently proposed fast simulation model, we assess the BER of the two coded OFDM systems in several realistic scenarios, taking into account Rayleigh and Rice channels, different mobile speeds, inner and outer channel coding, channel estimation, and one or two receive antennas. Our comparison shows that the DVB-T/H physical layer performance highly depends on the delay spread of the channel, whereas T-DMB is less sensitive to the frequency selectivity of the channel. As a result, DVB-T/H yields better performance than T-DMB in typical Rayleigh channels with significant delay spread. On the contrary, at high SNR, T-DMB outperforms DVB-T/H in Rice channels with low delay spread. As a side result, we show the performance improvement of DVB-H produced by MPE-FEC at the data link layer.      

基于PXA250的GPS,T-DMB智能手机方案实现

GPS,T-DMB功能现今已成为手机新功能应用的热点.从GPS技术、T-DMB技术和GSM等各功能模块的特点出发,介绍了一种低成本、多功能的智能手机的设计方案.在该手机方案设计上,充分利用PXA250的强大的处理能力,较简便地实现了GPS导航功能以及T-DMB电视接收功能,并阐述该款产品的硬件设计和软件设计实现.从优化软硬件设计的角度阐述如何以较低的成本来实现几项高端的手机功能.     

A Higher Data-Rate T-DMB System Based on a Hierarchical A-DPSK Modulation

Hierarchical modulation can be effectively used to enhance terrestrial digital multimedia broadcasting (T-DMB) or digital audio broadcasting (DAB) systems in response to both the demand for higher data-rate and the need to be backward compatible with legacy receivers. QAM-type modulations are well-liked for hierarchical transmission but require coherent detection based on pilot symbol aided channel estimation. In the T-DMB or the DAB system using DQPSK modulation, however, any available pilot symbols except for the phase reference symbol do not exist. Differential amplitude phase shift keying (DAPSK) modulation is easily applied to the T-DMB system for a hierarchical modulation but may be susceptible to fast fading. As a good candidate for a hierarchical modulation of T-DMB to solve the above problems, we propose an amplitude differential phase shift keying (A-DPSK) modulation which is robust to fast fading by estimating only amplitude coefficients of the channel transfer function with the use of amplitude pilots. To raise the accuracy of channel estimation, we arrange the amplitude pilots in a come-type and introduce a noise-reduction scheme of averaging estimated channel coefficients. Simulation results show that the proposed A-DPSK provides a good choice for achieving a higher data-rate over other possible modulation schemes for advanced T-DMB or DAB systems.      

A New Scheme to Predict Erasures for Reed-Solomon Decoder in T-DMB Receiver

In this paper, we introduce a new scheme to improve the performance of the terrestrial - digital multimedia broadcasting (T-DMB) system, which exploits the burst error characteristics at the output of the convolutional decoder and the properties of the Reed-Solomon (RS) decoder to correct more errors by predicting erasures in each RS packet in advance as many as possible before decoding in the RS decoder. Simulation results show that the proposed scheme yields performance gain of around 1 dB at BER of 10^-R which can result in the extended coverage area of the T-DMB system.