排序方式: 共有68条查询结果,搜索用时 15 毫秒
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随着可见光通信系统研究的不断发展,解决可见光通信上行通信链路缺失的问题日益引起重视。建立双向可见光通信系统,意味着在系统两端的收发器件上需要同时实现光电转换与电光转换。提出了以发光二极管(LED)同时作为光信号收发元件的实时双向可见光通信系统方案,设计了时分复用方式的LED双向工作控制机制,实现了双向可见光通信。在不同的收发端仰角下进行了实时双向通信系统的实验,实测结果表明本系统方案仅以LED作为光收发元件、不需严格对准和中继放大即可实现2 m以上距离、8 Mb/s速率的实时双向可见光通信。 相似文献
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A breaking wave can exert a great influence on the electromagnetic(EM) scattering result from sea surfaces. In this paper, the process of small-scale wave breaking is simulated by the commercial computational fluid dynamics(CFD)software FLUENT, and the backscattering radar cross section(RCS) of the turbulence structure after breaking is calculated with the method of moments. The scattering results can reflect the turbulent intensities of the wave profiles and can indicate high polarization ratios at moderate incident angles, which should be attributed to the incoherent backscatter from surface disturbance of turbulence structure. Compared with the wave profile before breaking, the turbulence structure has no obvious geometrical characteristic of a plunging breaker, and no sea spikes are present at large incident angles either.In summary, the study of EM scattering from turbulence structure can provide a basis to explain the anomalies of EM scattering from sea surfaces and help us understand the scattering mechanism about the breaking wave more completely. 相似文献
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A novel scheme for all-optical inverted wavelength conversion with 40-Gb/s pseudorandom bit sequences (PRBSs) based on a modified terahertz optical asymmetric demultiplexer (TOAD) is proposed. The performance of the proposed wavelength converter is analyzed in term of extinction ratio (ER) through numerical simulations. For a typical ER of 10 dB, some key characteristic parameters of the semiconductor optical amplifier (SOA) are designed. With the properly designed parameters, a high quality eye diagram is achievable, indicating that the amplitude fluctuation of the output signal is effectively reduced. 相似文献
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基于路径计算单元的光网络,根据无充足空闲资源用于无需流量迁移状态的恢复光路建立的背景,围绕故障恢复时尽量减少被中断连接的流量迁移过程,对并行的流量迁移过程进行了研究,建立了相应的数学模型,提出了并行流量迁移的实现方法,给出了可以得到并行流量迁移过程中连接新旧光路拆建顺序的启发式算法.文中提出的最小化最大中断连接资源需求数并行流量迁移算法包含依赖关系图分割算法和最小化最大中断连接资源需求数拆建顺序确定算法两大部分.仿真证明了最小化最大中断连接资源需求数并行流量迁移算法相对于普通串行流量迁移算法可以利用较少的额外中断得到迁移时间的大幅缩短. 相似文献