UEP with Adaptive Multilevel Embedded Modulation for MIMO-OFDM Systems
UEP with Adaptive Multilevel Embedded Modulation for MIMO-OFDM Systems
复制标题
用于 MIMO-OFDM 系统的具有自适应多级嵌入式调制的 UEP
DOI：
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发表时间：
2008
期刊：
影响因子：
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通讯作者：
W. Henkel
中科院分区：
文献类型：
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作者：
K. Hassan;W. Henkel
在本文中，考虑了具有不等误差概率（UEP）的可扩展多媒体系统。实施自适应调制和分层（嵌入式）星座的结合以实现三个不同级别的数据优先级。最高优先级数据位分布在所有可用的子载波上，并具有相对较低的调制顺序。根据给定的通道增益，将下一个数据级别嵌入在彼此顶部，从而形成不同的多级分层星座。在类之间考虑了任意的边距分离，但是应授予最高优先级数据（SER）一定的最大符号率。给定的数据速率使用最佳位载算法自适应分配。如果发生频道反馈错误，我们的算法非常接近理想情况，从而使高优先级数据甚至更安全。此外，低复杂的位加载算法使UEP适应概念适用于反馈有限的未来无线系统。
In this paper, a scalable multimedia system with unequal error probabilities (UEP) is considered. A combination of adaptive modulation and hierarchical (embedded) constellations is implemented to realize three different levels of data priorities. The highest priority data bits spread over all available subcarriers with a relatively low modulation order. The next data levels are embedded on top of each other, according to the given channel gain, forming varying multilevel hierarchical constellations. An arbitrary margin separation is considered between the classes, however the highest priority data should be granted a certain maximum symbol-error rate (SER). The given data rates are allocated adaptively using an optimum bitloading algorithm. In case of channel feedback errors, our algorithm performs very close to the ideal case, keeping the high priority data even safer. Moreover, the low-complex bit-loading algorithm makes the UEP adaptation concepts suitable for future wireless systems with limited feedback.