Conditional access system (CAS) is a key technical component in digital TV broadcasting through which TV op-erators manage the appropriate rights of different subscribers in order to protect their commercial benefits....Conditional access system (CAS) is a key technical component in digital TV broadcasting through which TV op-erators manage the appropriate rights of different subscribers in order to protect their commercial benefits. The normal digital TV receiver can only receive and decode the pay TV programs scrambled by one specific CAS. In this paper, the authors proposed a smartcard conditional access interface (SCAI) scheme in order to make the digital TV receiver be a common receiving platform independent of any specific CAS employed at the broadcasting head-end. As a result, it only needs to include a common condi-tional access software package (CCAP) without any requirement of hardware modification in the receiver. Comparison between the two mentioned DVB-CI-based schemes showed that the cost of such kind receiver is greatly reduced. The main design points of the proposed scheme and its reference implementation’s architecture are presented in this paper. This scheme is also one of the candidate national standards for Chinese digital TV broadcasting industry.展开更多
The fundamental aspects of digital broadcasting are its service flexibility and power savings, which make all-digital satellite broadcasting a viable and economic propositon compared with analog broadcasting. Tendenci...The fundamental aspects of digital broadcasting are its service flexibility and power savings, which make all-digital satellite broadcasting a viable and economic propositon compared with analog broadcasting. Tendencies in the development of digital television broadcasting are: (1) Stereophonic or two-language sound transmission with television in existing analog TV system, (2) Digital direct satellite broadcasting (D-DBS); (3)Digital high definition television (HDTV) Broadcasting.展开更多
Digital broadcasting is a novel paradigm for the next generation broadcasting. Its goal is to provide not only better quality of pictures but also a variety of services that is impossible in traditional airwaves broad...Digital broadcasting is a novel paradigm for the next generation broadcasting. Its goal is to provide not only better quality of pictures but also a variety of services that is impossible in traditional airwaves broadcasting. One of the important factors for this new broadcasting environment is the interoperability among broadcasting applications since the environment is distributed. Therefore the broadcasting metadata becomes increasingly important and one of the metadata standards for a digital broadcasting is TV-Anytime metadata. TV-Anytime metadata is defined using XML schema, so its instances are XML data. In order to fulfill interoperability, a standard query language is also required and XQuery is a natural choice. There are some researches for dealing with broadcasting metadata. In our previous study, we have proposed the method for efficiently managing the broadcasting metadata in a service provider. However, the environment of a Set-Top Box for digital broadcasting is limited such as low-cost and low-setting. Therefore there are some considerations to apply general approaches for managing the metadata into the Set-Top Box. This paper proposes a method for efficiently managing the broadcasting metadata based on the Set-Top Box and a prototype of metadata management system for evaluating our method. Our system consists of a storage engine to store the metadata and an XQuery engine to search the stored metadata and uses special index for storing and searching. Our two engines are designed independently with hardware platform therefore these engines can be used in any low-cost applications to manage broadcasting metadata.展开更多
广播电视同步数字体系(Synchronous Digital Hierarchy,SDH)数字微波传输系统在远距离、大容量传输等方面有着天然的技术优势,但由于传输过程中需要完成适配、复用和中继等信号处理步骤,导致系统运行时极易出现故障现象。因此,围绕SDH...广播电视同步数字体系(Synchronous Digital Hierarchy,SDH)数字微波传输系统在远距离、大容量传输等方面有着天然的技术优势,但由于传输过程中需要完成适配、复用和中继等信号处理步骤,导致系统运行时极易出现故障现象。因此,围绕SDH数字微波传输系统的设备组成、工作原理及功能模块展开深入研究,分析论证系统运行中常见的故障,解析故障原因并给出处置策略,以期为技术人员提供参考,提升广播电视SDH数字微波传输系统的稳定性和可靠性。展开更多
基金Project (No. 200442) supported by the Electronics DevelopmentFoundation for the Key Industrialization Project of the Ministry of0Information Industry, China
文摘Conditional access system (CAS) is a key technical component in digital TV broadcasting through which TV op-erators manage the appropriate rights of different subscribers in order to protect their commercial benefits. The normal digital TV receiver can only receive and decode the pay TV programs scrambled by one specific CAS. In this paper, the authors proposed a smartcard conditional access interface (SCAI) scheme in order to make the digital TV receiver be a common receiving platform independent of any specific CAS employed at the broadcasting head-end. As a result, it only needs to include a common condi-tional access software package (CCAP) without any requirement of hardware modification in the receiver. Comparison between the two mentioned DVB-CI-based schemes showed that the cost of such kind receiver is greatly reduced. The main design points of the proposed scheme and its reference implementation’s architecture are presented in this paper. This scheme is also one of the candidate national standards for Chinese digital TV broadcasting industry.
文摘The fundamental aspects of digital broadcasting are its service flexibility and power savings, which make all-digital satellite broadcasting a viable and economic propositon compared with analog broadcasting. Tendencies in the development of digital television broadcasting are: (1) Stereophonic or two-language sound transmission with television in existing analog TV system, (2) Digital direct satellite broadcasting (D-DBS); (3)Digital high definition television (HDTV) Broadcasting.
文摘Digital broadcasting is a novel paradigm for the next generation broadcasting. Its goal is to provide not only better quality of pictures but also a variety of services that is impossible in traditional airwaves broadcasting. One of the important factors for this new broadcasting environment is the interoperability among broadcasting applications since the environment is distributed. Therefore the broadcasting metadata becomes increasingly important and one of the metadata standards for a digital broadcasting is TV-Anytime metadata. TV-Anytime metadata is defined using XML schema, so its instances are XML data. In order to fulfill interoperability, a standard query language is also required and XQuery is a natural choice. There are some researches for dealing with broadcasting metadata. In our previous study, we have proposed the method for efficiently managing the broadcasting metadata in a service provider. However, the environment of a Set-Top Box for digital broadcasting is limited such as low-cost and low-setting. Therefore there are some considerations to apply general approaches for managing the metadata into the Set-Top Box. This paper proposes a method for efficiently managing the broadcasting metadata based on the Set-Top Box and a prototype of metadata management system for evaluating our method. Our system consists of a storage engine to store the metadata and an XQuery engine to search the stored metadata and uses special index for storing and searching. Our two engines are designed independently with hardware platform therefore these engines can be used in any low-cost applications to manage broadcasting metadata.
文摘对广播电视无线数字化系统中应用到的多项核心技术进行了深入剖析和探讨。首先,分析调制技术,介绍了调频(Frequency Modulation,FM)/调幅(Amplitude Modulation,AM)调制的原理,并阐述了数字调制技术如正交幅度调制(Quadrature Amplitude Modulation,QAM)、正交频分多址(Orthogonal Frequency Division Multiple Access,OFDMA)等的工作机制与优势。其次,探讨数字电视广播的传输技术,包括地面数字电视传输标准和卫星传输技术。再次,重点分析音视频编码、信道编码等信号处理技术,说明它们在压缩数据、抗干扰方面的作用。最后,介绍多频网(Multi Frequency Network,MFN)和单频网(Single Frequency Network,SFN)两种网络配置方式的不同。通过应用这些技术,我国已构建起规模庞大、技术先进的广播电视无线发射网络,为人们获取音、视频信息提供保障。
文摘广播电视同步数字体系(Synchronous Digital Hierarchy,SDH)数字微波传输系统在远距离、大容量传输等方面有着天然的技术优势,但由于传输过程中需要完成适配、复用和中继等信号处理步骤,导致系统运行时极易出现故障现象。因此,围绕SDH数字微波传输系统的设备组成、工作原理及功能模块展开深入研究,分析论证系统运行中常见的故障,解析故障原因并给出处置策略,以期为技术人员提供参考,提升广播电视SDH数字微波传输系统的稳定性和可靠性。
