The Twin-Loop Antenna(TLA)has been widely used because of itsbroadband property and simply feeding,and some modified structures have been devel-oped from its prototype by Chinese engineers.But the exact design theory ...The Twin-Loop Antenna(TLA)has been widely used because of itsbroadband property and simply feeding,and some modified structures have been devel-oped from its prototype by Chinese engineers.But the exact design theory for TLA accord-ing to the impedance calculation has not yet been published.In this paper,the impedanceof loop in a TLA is analysed and computed by using the method of moments,and the de-sign formulae and a two-step optimization program for extending the bandwidth of inputimpedance of TLA are detailed.An example of optimized design shows that the bandwidthcan be increased up to 36.4% for VSWR≤1.10,which is wider than the bandwidth of ra-diation pattern.展开更多
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
October 24,2006, China SARFT (State Administration of Radio Film and Television) formally issued the China mobile multimedia broadcasting (namely, Mobile TV) industry standard. The standard is a STiMi standard self-de...October 24,2006, China SARFT (State Administration of Radio Film and Television) formally issued the China mobile multimedia broadcasting (namely, Mobile TV) industry standard. The standard is a STiMi standard self-developed in China and put into practice from No-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
对于广播电视制播工程项目,为确保直播内容安全播出和内容编辑的时效性,与直播相关的系统和内容编辑系统的核心设备需要接入不间断电源(Uninterruptible Power Supply,UPS)供电回路。因此,在供配电系统设计过程中,如何选择合适的UPS电...对于广播电视制播工程项目,为确保直播内容安全播出和内容编辑的时效性,与直播相关的系统和内容编辑系统的核心设备需要接入不间断电源(Uninterruptible Power Supply,UPS)供电回路。因此,在供配电系统设计过程中,如何选择合适的UPS电源设备技术架构成为一个关键问题。主要探讨了广播电视制播工程项目中UPS电源设备的选用,对UPS高频机和UPS工频机进行了比较分析,进而给出了广播电视制播工程中UPS电源设备的选用策略。展开更多
文摘The Twin-Loop Antenna(TLA)has been widely used because of itsbroadband property and simply feeding,and some modified structures have been devel-oped from its prototype by Chinese engineers.But the exact design theory for TLA accord-ing to the impedance calculation has not yet been published.In this paper,the impedanceof loop in a TLA is analysed and computed by using the method of moments,and the de-sign formulae and a two-step optimization program for extending the bandwidth of inputimpedance of TLA are detailed.An example of optimized design shows that the bandwidthcan be increased up to 36.4% for VSWR≤1.10,which is wider than the bandwidth of ra-diation pattern.
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October 24,2006, China SARFT (State Administration of Radio Film and Television) formally issued the China mobile multimedia broadcasting (namely, Mobile TV) industry standard. The standard is a STiMi standard self-developed in China and put into practice from No-
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.
文摘对于广播电视制播工程项目,为确保直播内容安全播出和内容编辑的时效性,与直播相关的系统和内容编辑系统的核心设备需要接入不间断电源(Uninterruptible Power Supply,UPS)供电回路。因此,在供配电系统设计过程中,如何选择合适的UPS电源设备技术架构成为一个关键问题。主要探讨了广播电视制播工程项目中UPS电源设备的选用,对UPS高频机和UPS工频机进行了比较分析,进而给出了广播电视制播工程中UPS电源设备的选用策略。
