Advanced television systems for terrestrial broadcasting: Some problems and some proposed solutions
Advanced television systems for terrestrial broadcasting: Some problems and some proposed solutions
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DOI：
10.1109/5.387095
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发表时间：
1995-06
期刊：
影响因子：
--
通讯作者：
W. Schreiber
中科院分区：
文献类型：
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作者：
W. Schreiber
本白皮书的第一部分讨论了新的电视广播系统必须满足的要求，以使其最大限度地被各种利益相关者接受，包括广播公司、设备制造商、节目制作人、监管机构和观众。最重要的性能因素是无线频谱的有效使用、覆盖与质量、成本、互操作性以及实际过渡方案的存在。结论是，所有的接收器不需要具有相同的性能，并且必须为家庭中的非关键位置提供低成本的接收器。如果通过适当的系统设计使价格和性能的这种变化成为可能，那么互操作性就会得到促进，随着时间的推移，就有可能像联邦通信委员会所希望的那样，实现无中断的改进。在论文的第二部分中，讨论了可能允许满足这些要求的技术。其中包括联合多分辨率信源和信道编码、多载波调制以及模拟/数字混合编码和传输。对模拟变换系数进行扩频处理，并对要通过信道传输的复数混合符号应用编码的正交频分多路复用(COFDM)。比较了均衡和改善噪声、干扰和多径抑制的各种方法。最后给出了一个系统的实例，该系统利用所讨论的一些技术来满足不同的需求。该系统提供更大的覆盖范围，尽管质量低于目前提议的全数字系统，但在其大部分服务领域与此类系统的质量相当或更高。它还具有根据信号质量和接收器特性在每个接收器上进行自我优化的特点，并有助于为不太关键的应用设计成本和性能更低的接收器。>；
The first part of this paper discusses the requirements that must be met by a new television broadcasting system to maximize its acceptability to the various stakeholders, including broadcasters, equipment manufacturers, program producers, regulatory authorities, and viewers. The most important performance factors are efficient use of over-the-air spectrum, coverage versus quality, cost, interoperability, and the existence of a practical transition scenario. It is concluded that all receivers need not have the same peformance, and that low-cost receivers must be available for noncritical locations in the home. If this variation in price and performance is made possible by appropriate system design, then interoperability is facilitated and nondisruptive improvement over time is made possible, as desired by the Federal Communications Commission. In the second part of the paper, techniques that may permit meeting these requirements are discussed. These include joint multiresolution source and channel coding, multicarrier modulation, and hybrid analog/digital coding and transmission. The analog transform coefficients are subjected to spread-spectrum processing, and coded orthogonal frequency-division multiplex (COFDM) is applied to the complex hybrid symbols to be transmitted through the channel. Various methods of equalization and of improving noise, interference, and multipath rejection are compared. Finally, an example is given of a system that meets the various requirements by making use of a number of the techniques discussed. The system provides extended coverage, albeit at lower quality than currently proposed all-digital systems, and equal or higher quality than such systems in much of their service area. It also features self-optimization at each receiver depending on signal quality and receiver characteristics, and facilitates the design of receivers of lower cost and performance for less-critical applications. >