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This paper provides an in-depth view of Terahertz Band (0.1–10 THz) communication, which is envisioned as a key technology to satisfy the increasing demand for higher speed wireless communication. THz Band communication will alleviate the spectrum scarcity and capacity limitations of current wireless systems, and enable new applications both in classical networking domains as well as in novel nanoscale communication paradigms. In this paper, the device design and development challenges for THz Band are surveyed first. The limitations and possible solutions for high-speed transceiver architectures are highlighted. The challenges for the development of new ultra-broadband antennas and very large antenna arrays are explained. When the devices are finally developed, then they need to communicate in the THz band. There exist many novel communication challenges such as propagation modeling, capacity analysis, modulation schemes, and other physical and link layer solutions, in the THz band which can be seen as a new frontier in the communication research. These challenges are treated in depth in this paper explaining the existing plethora of work and what still needs to be tackled. 相似文献
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Martin Nordal Petersen Roeland Nuijts Lars Lange Bjørn 《Fiber and Integrated Optics》2014,33(3):224-231
AbstractThis article presents an advanced optical model for simulation of alien wavelengths in multi-domain and multi-vendor dense wavelength-division multiplexing networks. The model aids optical network planners with a better understanding of the non-linear effects present in dense wavelength-division multiplexing systems and better utilization of alien wavelengths in future applications. The limiting physical effects for alien wavelengths are investigated in relation to power levels, channel spacing, and other factors. The simulation results are verified through experimental setup in live multi-domain dense wavelength-division multiplexing systems between two national research networks: SURFnet in Holland and NORDUnet in Denmark. 相似文献
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在合理选择通信系统参量和通信信道参量的基础上,利用Monte Carlo方法模拟了卫星接收到的水下平台上行激光通信信号.分析了卫星接收信号的空间和时间分布特性,以及与望远镜接收视场角的关系,并计算了接收信号的信噪比,得出了3°望远镜视场角和15 μs信号积分时间的优化参量.基于计算结果,根据激光脉冲的PPM调制方式和最大似然检测方法,计算了系统的通信误码率,同时分析了海气界面、云等传输介质对通信的影响.研究结果表明:根据文中给定通信系统参量,在典型海水、海气界面、云等环境条件下,卫星与激光信号中心水平距离5 km范围内信号误码率<10-4.因此位于水下60 m的水下平台可能实现对卫星上行激光通信. 相似文献
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The evolution of the previous mobile communication generations has led to innovative goals of the Internet of Everything (IoE) in the 5G. However, addressing all IoE-associated problems in 5G is difficult and a long-term process. As the key performance indicators (KPIs) of the 5G services are highly diverse, it is an intimidating task to develop a single platform enabling all KPIs. The vision of next-generation 6G wireless communications lies not only in enhancing these targets but also in providing new services. Numerous extensively envisaged future services, including life-critical services and wireless brain–computer interactions, will be critically dependent on an instant, virtually unlimited wireless connectivity. In this direction, the 6G is envisioned to have primely five service objectives; further-enhanced mobile broadband (FeMBB), ultra-massive machine type communication (umMTC), extremely reliable low latency communication (ERLLC), long-distance and high-mobility communications (LDHMC), and extremely low-power communications (ELPC). The 3D global integration of the wireless communication networks is lacking in the 5G, which is targeted by the future 6G. In this paper, we present an exhaustive review of the 6G wireless communication network. We explore the various existing mobile communication generations concerning data rate, frequency band, bandwidth allotted, latency, and applications. We also highlight various current trends and issues in the 5G communication network, which drives research for the 6G communication network. Our focus is to provide a comprehensive survey on the future 6G. So, we explored the objectives and design principles for 6G. This paper highlights the key 6G technology drivers. This paper also proposes an architectural design for 6G. Moreover, we carry out a case-study of 6G architecture operational design and compare the result with previous generation architecture designs. Further, 6G envisioned open research challenges, research directions, and recent advancements are also highlighted in this paper. Furthermore, we discuss possible use-cases in terms of real-time interactions of the biological, physical, and digital world, and also how these use-cases are going to serve in 6G. 相似文献
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设计了一种具有独特双透镜外腔结构的可调谐窄线宽激光器,利用一个温控50 GHz的标准具提供ITU标准波长序列,通过一个压电陶瓷驱动的Fabry-Pérot可调谐滤波器选择一个标准波长实现单波长输出。实验结果表明:该激光器的调谐范围达到了1 525~1 580 nm,覆盖整个C波段,线宽为37.5 kHz,400 mA电流条件下的输出功率超过50 mW,边模抑制比超过50 dB,达到或超过相干通讯应用的要求和其他单片集成类器件的指标。另外,本结构具有位置容差大、调谐速度快(<3 ms)、易于实现超窄线宽以及波长微调等优点,待实现小型化和标准封装,其大规模应用将成为可能。 相似文献
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穿过大气湍流的高斯激光脉冲在时间域的展宽行为与高斯脉冲通过理想高斯滤波器后的时域展宽行为相似。因此,为了激光通信信道仿真的需要,提出用级联巴特沃斯滤波器来逼近理想高斯滤波器的方法对这种时间域上的展宽行为进行建模。逼近后的高斯滤波器的3dB频率点与大气湍流的物理参数(包括折射率结构常数和湍流外尺度)和传播几何路径长度联系在一起,从而将高斯脉冲的展宽与所通过的大气湍流环境参数相结合并得到了模拟高斯脉冲展宽的解析表达式。该模型和由模型参数表示的高斯脉冲展宽的解析表达式不仅在湍流弱起伏区有效,而且在从弱起伏到中等起伏再到强起伏的整个区域中都有效。 相似文献
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