共查询到19条相似文献,搜索用时 156 毫秒
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介绍了贵州广播电视台卫视频道高清播出系统的设计与实施情况.详细介绍了高清缩编系统、高清播出系统、高标清同播设计、各子系统互联设计等几个部分,分别阐述了各部分功能设计及系统特点和亮点.该高清播出系统运行近半年,有着高质量、高安全可靠、易维护、易扩展等特点. 相似文献
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本文对江苏省广播电视总台卫视高清频道设计和建设过程进行了总体描述.重点分析了高清演播室制作、后期编辑、播出传输的相关技术和流程. 相似文献
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本文对江苏省广播电视总台卫视高清频道设计和建设过程进行了总体描述。重点分析了高清演播室制作、后期编辑、播出传输的相关技术和流程。 相似文献
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贵州广播电视台SDH传输系统 总被引:3,自引:3,他引:0
遵循国家广电总局62号令对广播电视安全播出的规定,按照新形势下对电视节目提出的更高要求,并综合考虑贵州广播电视台事业的发展以及传输业务的不断增加,设计了SDH传输系统。该系统的设计思路和系统构成特点具有超前意识,解决了贵州广播电视台原传输系统中存在的安全隐患和带宽枯竭问题,保证了节目的安全传输,满足了节目高标清同播的传输要求。 相似文献
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An efficient space-frequency coded OFDM system for broadband wireless communications 总被引:1,自引:0,他引:1
We propose an efficient space-frequency coded orthogonal frequency-division multiplexing (OFDM) system for high-speed transmission over wireless links. The analytical expression for the pairwise probability of the proposed space-frequency coded OFDM system is derived in slow, space- and frequency-selective fading channels. The design criteria of trellis codes used in the proposed system are then developed and discussed. It is shown that the proposed space-frequency coded OFDM can efficiently achieve the full diversity provided by the fading channel with low trellis complexity, while for traditional space-frequency coded OFDM systems, we need to design space-time trellis codes with high trellis complexity to exploit the maximum achievable diversity order. The capacity properties of space-frequency coded OFDM over multipath fading channels are also studied. Numerical results are provided to demonstrate the significant performance improvement obtained by the proposed space-frequency coded OFDM scheme, as well as the excellent outage capacity properties. 相似文献
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数字高清电视转播车作为移动式演播室系统在广电行业已经广泛使用,以12信道数字高清电视转播车为例,介绍了高清电视转播车视频系统构成,阐述了系统的设计原则以及视频系统、PFU微波传送设备、同步系统的选型和配置、应急方案等。 相似文献
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Delogne P. Poncin O. Caillie B.V. Vandendorpe L. 《Selected Areas in Communications, IEEE Journal on》1993,11(1):146-152
A compatible coding scheme for interlaced HDTV (high-definition television) is proposed. This scheme provides a standard definition signal and a second channel containing the additional information required to reach the HD resolution. The global scheme is of the pyramidal type: the standard TV is obtained by downsampling the HDTV signal by means of a field-based operation. The standard TV signal is coded, decoded, and upsampled. It is used as a prediction of the HD signal and the prediction error is coded in a second channel. In both branches, motion-compensated hybrid DCT coding is used. In addition, the DCT is taken within the frame 相似文献
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Yong Sun Zixiang Xiong Xiaodong Wang 《Wireless Communications and Mobile Computing》2006,6(8):1057-1075
In this paper, we consider progressive image transmission over differentially space‐time coded orthogonal frequency‐division multiplexing (OFDM) systems and treat the problem as one of optimal joint source‐channel coding (JSCC) in the form of unequal error protection (UEP), as necessitated by embedded source coding (e.g., SPIHT and JPEG 2000). We adopt a product channel code structure that is proven to provide powerful error protection and employ low‐complexity decision‐feedback decoding for differentially space‐time coded OFDM without assuming channel state information. For a given SNR, the BER performance of the differentially space‐time coded OFDM system is treated as the channel condition in the JSCC/UEP design via a fast product code optimization algorithm so that the end‐to‐end quality of reconstructed images is optimized in the average minimum MSE sense. Extensive image transmission experiments show that SNR/BER improvements can be translated into quality gains in reconstructed images. Moreover, compared to another non‐coherent detection algorithm, i.e., the iterative receiver based on expectation‐maximization algorithm for the space‐time coded OFDM systems, differentially space‐time coded OFDM systems suffer some quality loss in reconstructed images. With the efficiency and simplicity of decision‐feedback differential decoding, differentially space‐time coded OFDM is thus a feasible modulation scheme for applications such as wireless image over mobile devices (e.g., cell phones). Copyright © 2006 John Wiley & Sons, Ltd. 相似文献