Fast and Efficient Adaptation Algorithms for Multi-Gigabit Wireless Infrared Systems
Fast and Efficient Adaptation Algorithms for Multi-Gigabit Wireless Infrared Systems
复制标题
适用于多千兆位无线红外系统的快速高效的自适应算法
DOI：
10.1109/jlt.2013.2286743
复制
发表时间：
2013
影响因子：
4.7
通讯作者：
J. Elmirghani
中科院分区：
文献类型：
--
作者：
F. Alsaadi;Mohammed A. Alhartomi;J. Elmirghani
多波束角度自适应系统 (MBAAS) 已被证明可以比传统的点扩散光学无线系统提供性能改进。然而，这会导致计算成本的增加。本文介绍了一种通过有效使用分而治之算法来加速适应过程的方法，通过递归地分解扫描过程并将其集中到每次迭代中的较小区域。新的、快速且高效的角度自适应算法具有优化光点的数量和图案（位置）的优点，从而最大化接收器的信噪比（SNR），无论发射器的位置、接收器的方向及其视场如何。它还可以适应环境变化，提供针对阴影和信号阻塞的强大链接。此外，还使用波束延迟自适应方法来减少多径色散和符号间干扰的影响。角度和延迟自适应的组合增加了链路设计的自由度，从而产生紧凑的脉冲响应和能够实现更高数据速率（15 Gbit/s）的系统。信噪比显着提高，光学无线信道带宽超过 15 GHz，并且在存在阴影的现实环境中以 15 Gbit/s 的速度运行时考虑了人眼安全，具有完全移动性。
Multibeam angle adaptive systems (MBAAS) have been shown to offer performance improvements over traditional spot-diffusing optical wireless systems. However, an increase in the computational cost is incurred. This paper introduces a method to speed up the adaptation process through efficient use of a divide and conquer algorithm by recursively breaking down the scanning process and focusing it into a smaller region in each iteration. The new, fast and efficient angle adaptation algorithm offers the advantages of optimizing the number and pattern (positions) of the spots so as to maximize the receiver's signal-to-noise ratio (SNR), regardless of the transmitter's position, the receiver's orientation and its field of view. It can also adapt to environmental changes, providing a robust link against shadowing and signal blockage. Furthermore, a beam delay adaptation method is used to reduce the effect of multipath dispersion and inter-symbol interference. The combination of angle and delay adaptation adds a degree of freedom to the link design, resulting in a compact impulse response and a system that is able to achieve higher data rates (15 Gbit/s). Significant improvements in the SNR, with optical wireless channel bandwidths of more than 15 GHz are obtained, and eye safety is considered while operating at 15 Gbit/s with full mobility in a realistic environment where shadowing exists.