检索结果-内蒙古大学图书馆

Generic evaluation of FSO system over Malaga turbulence channel with MPPM and non-zero-boresight pointing errors

IET COMMUNICATIONS 2020年第18期14卷 3294-3302页

作者： Alshaer, Nancy Ismail, Tawfik Nasr, Mohamed E. Tanta Univ Fac Engn Gharbia Egypt Cairo Univ Natl Inst Laser Enhanced Sci Giza Egypt Nile Univ Wireless Intelligent Networks Ctr WINC Giza Egypt

Free space optical (FSO) communication channels are affected by fluctuations in irradiance due to atmospheric turbulence and pointing errors. Recently, a generalized statistical model knows as Malaga (M) was developed to describe irradiance fluctuations of the beam propagating through a turbulent medium. In this paper, an approximate finite-series probability density function (PDF) for composite M turbulence with pointing errors is verified. Considering multiple pulse-position-modulation (MPPM) with intensity modulation and direct detection, specific closed-form expressions for average symbol error rate (ASER) and outage probability are obtained. Moreover, asymptotic expressions for ASER and outage probability over the Malaga channel with pointing errors are presented. Finally, ASER and outage probability expressions are deduced in three turbulence regimes, strong, moderate, and weak. Therefore, simulation results are given to confirm the accuracy of the proposed expressions. The results show that the optimum beam divergence angle is 1 mrad for zero-boresight displacement and 2 mrad for nonzero-boresight at a distance of 1 km. By increasing the range to 5 km, atmospheric turbulence is found to have the dominant effect over boresight displacement. Moreover, the system performance at the optimized divergence angle is studied in terms of transmit power, normalized boresight, and link distance.

关键词： probability pulse position modulation optical links atmospheric turbulence error statistics intensity modulation signal detection optical modulation free-space optical communication atmospheric light propagation telecommunication network reliability FSO system Málaga turbulence channel MPPM nonzero-boresight pointing errors free-space optical communication channels atmospheric turbulence generalised statistical model optical beam propagation turbulent medium irradiance fluctuation conditions approximate finite series probability density function multiple pulse position modulation closed-form expressions ASER outage probability asymptotic expressions turbulence regimes turbulence model zero boresight displacement intensity modulation and direct detection average symbol error rate optimum beam divergence angle

来源：评论

学校读者我要写书评

暂无评论

Optical comb generator with flat-topped spectral response using one electroabsorption-modulated laser and one phase modulator

引用

OPTICAL ENGINEERING 2020年第1期59卷 016112-016112页

作者： Li, Yitong Zhou, Wen Chen, You-Wei Chen, Yuanxiang Huang, Yongtao Li, Kaile Yu, Jianguo Chang, Gee-Kung Beijing Univ Posts & Telecommun Sch Elect Engn Beijing Peoples R China Georgia Inst Technol Sch Elect & Comp Engn Atlanta GA 30332 USA

We experimentally demonstrated a novel structure for generating an optical frequency comb source for multicarrier modulation in an optical transmission system. In the proposed scheme, the integration of an electroabsorption-modulated laser cascaded with a phase modulator is employed, both of which are driven and synchronized via a common sinusoidal radio frequency signal. The optimal operating range defined as a spectral flatness with less than 3-dB power fluctuation can be obtained through numerical simulation. Using the proposed scheme, we can achieve 10 flat-topped and frequency-locked optical carriers with a 12.5-GHz frequency spacing. On-off-keying intensity-modulated signals with 3.125 and 12.5 Gb/s are transmitted error-free over 20 km standard single-mode fiber utilizing the proposed optical frequency comb source for an optical wavelength-division multiplexing transmission system. (C) 2020 Society of Photo-Optical Instrumentation Engineers (SPIE)

关键词： phase modulator electroabsorption modulator intensity modulation and direct detection optical frequency comb source

来源：评论

学校读者我要写书评

暂无评论

Adaptive Channel-Matched detection for C-Band 64-Gbit/s Optical OOK System Over 100-km Dispersion-Uncompensated Link

引用

JOURNAL OF LIGHTWAVE TECHNOLOGY 2020年第18期38卷 5048-5055页

作者： Wang, Haide Zhou, Ji Guo, Dong Feng, Yuanhua Liu, Weiping Yu, Changyuan Li, Zhaohui Jinan Univ Dept Elect Engn Coll Informat Sci & Technol Guangzhou 510632 Peoples R China Beijing Inst Technol Sch Informat & Elect Beijing 100081 Peoples R China Hong Kong Polytech Univ Dept Elect & Informat Engn Hong Kong Peoples R China Sun Yat Sen Univ State Key Lab Optoelect Mat & Technol Sch Elect & Informat Technol Guangzhou 510275 Peoples R China Southern Marine Sci & Engn Guangdong Lab Zhuhai Zhuhai 519000 Peoples R China

In this paper, we propose adaptive channel-matched detection (ACMD) to effectively compensate channel distortions for C-band 64-Gbit/s intensity-modulation and direct-detection (IM/DD) optical on-off keying (OOK) system over a 100-km dispersion-uncompensated link. The proposed ACMD can adaptively compensate most of the link distortions based on channel and noise characteristics, which includes a polynomial nonlinear equalizer (PNLE), a decision feedback equalizer (DFE) and maximumlikelihood sequence estimation (MLSE). Based on the channel characteristics, PNLE eliminates the linear and nonlinear distortions, while the followedDFEcompensates the spectral nulls caused by chromatic dispersion. Finally, based on the noise characteristics, a post filter can whiten the noise for implementing optimal signal detection using MLSE. To the best of our knowledge, we present a record C-band 64-Gbit/s IM/DD opticalOOKsystem over a 100km dispersion-uncompensated link achieving 7% hard-decision forward error correction limit using only the proposed ACMD at the receiver side.

关键词： Adaptive channel-matched detection C-band chromatic dispersion intensity modulation and direct detection on-off keying

来源：评论

学校读者我要写书评

暂无评论

120 GBaud PAM-4/PAM-6 Generation and detection by Photonic Aided Digital-to-Analog Converter and Linear Equalization

引用

JOURNAL OF LIGHTWAVE TECHNOLOGY 2020年第8期38卷 2226-2230页

作者： Xin, Haiyun Kong, Deming Zhang, Kuo Jia, Shi Zhang, Xiaoling Hu, Weisheng Hu, Hao Shanghai Jiao Tong Univ Shanghai Inst Adv Commun & Data Sci State Key Lab Adv Opt Commun Syst & Networks Shanghai 200240 Peoples R China Tech Univ Denmark DTU Foton DK-2800 Lyngby Denmark Univ Elect Sci & Technol China Sch Commun & Informat Engn Educ Minist China Key Lab Opt Fiber Sensing & Commun Chengdu 611731 Sichuan Peoples R China

In this article, for the first time, we propose a photonic-aided digital-to-analog converter (PA-DAC) to break through transmitter-side bandwidth limitation in intensity modulation and direct detection (IM-DD) systems. By using this method, bandwidth of receiver-side devices can be fully utilized, and nonlinear distortions in high-data-rate electrical signals are avoided. Experimental results show that, with only linear equalization, 120 GBaud PAM-4 and PAM-6 signals have been successfully generated and detected with bite error ratios (BERs) below 6.25%-OH HD-FEC and 20%-OH SD-FEC limits, respectively.

关键词： intensity modulation and direct detection linear equalization optical interconnects photonic aided digital-to-analog converter pulse amplitude modulation

来源：评论

学校读者我要写书评

暂无评论

Successive Interference Cancellation for Power Switched, Non-Synchronized Signals 12

Successive Interference Cancellation for Power Switched, Non...

引用

12th International Symposium on Communication Systems, Networks and Digital Signal Processing (CSNDSP)

作者： Stevens, Nobby Katholieke Univ Leuven ESAT DRAMCO Ghent Belgium

ISBN: (纸本)9781728167435

This work presents a novel method to demultiplex intensity modulated, non-synchronized power switched signals. Based on the frequency domain properties of the transmitted waves, the method enables determination of the random delay and channel attenuation of each contributing source individually at the receiver side. The algorithm is particularly attractive to be applied for visible light positioning, as contemporary illumination infrastructures do not provide a means of synchronization between the different lighting points, while power switching is often used for dimming purposes.

关键词： Demultiplexing visible light positioning intensity modulation and direct detection

来源：评论

学校读者我要写书评

暂无评论

System aspects of the next-generation data-center networks based on 200G per lambda IMDD links 3

System aspects of the next-generation data-center networks b...

引用

Conference on Metro and Data Center Optical Networks and Short-Reach Links III

作者： Wei, Jinlong Calabro, Stefano Rahman, Talha Stojanovic, Nebojsa Huawei Technol Duesseldorf GmbH European Res Ctr Munich Germany

ISBN: (纸本)9781510633803

Following the standardization of 400 Gigabit Ethernet for data center networks (DCN), the industry will need 800 Gigabit or 1.6 Terabit pluggable modules soon after 2020. 200G per lambda directly detected links are very promising solutions to achieve the best trade-off between cost, size, and power. This paper investigates the challenges of 200G per lambda in DCN, due to the component bandwidth and noise limitations, and shows the technical feasibility enabled by advanced modulation formats and digital signal processing.

关键词： 800 Gigabit Ethernet data center networks optical fiber communications intensity modulation and direct detection advanced modulations link power budget digital signal processing

来源：评论

学校读者我要写书评

暂无评论

ANN-based channel estimation algorithm of IM/DD-OFDM/OQAM-PON systems with mobile fronthaul network in 5G

引用

OPTICAL FIBER TECHNOLOGY 2020年 59卷 102310-102310页

作者： Liang, Siyuan Zhao, Fangli Zhao, Feng Huang, Yijie Wang, Congyi Xian Univ Posts & Telecommun Shaanxi Key Lab Informat Commun Network & Secur Xian 710121 Peoples R China

5G mobile fronthaul (MFH) network requires data transmission with large bandwidth and ultra-low latency. Orthogonal frequency division multiplexing/offset quadrature amplitude modulation (OFDM/OQAM) passive optical network (PON) system is the 5G MFH solution with low spectrum efficiency and large bandwidth. The OFDM/OQAM-PON transmission performance will be undermined by intrinsic imaginary interference (IMI) induced by chromatic dispersion (CD) and polarization mode dispersion (PMD). In this paper, we proposed an artificial neural network (ANN) based channel estimation (CE) algorithm, which can effectively reduce IMI by estimation of channel transfer function (TF). Simulation results show that the proposed algorithm can optimize the system performance, compared with the conventional LS method, the proposed algorithm can improve bit error rate optimization capability by an order of magnitude.

关键词： Orthogonal frequency division multiplexing/offset quadrature amplitude modulation (OFDM/OQAM) Passive optical network (PON) intensity modulation and direct detection Channel estimation (CE) Artificial neural network (ANN)

来源：评论

学校读者我要写书评

暂无评论

Enhanced Optical-OFDM With Index and Dual-Mode modulation for Optical Wireless Systems

引用

IEEE ACCESS 2020年 8卷 128646-128664页

作者： Azim, Ali Waqar Le Guennec, Yannis Chafii, Marwa Ros, Laurent Univ Grenoble Alpes CNRS Inst Engn Grenoble INPGIPSA LAB F-38000 Grenoble France CY Cergy Paris Univ UMR 8051 ETIS ENSEACNRS F-95000 Cergy France

In this article, we introduce intensity modulation and direct detection compatible enhanced optical-orthogonal frequency division multiplexing with index modulation (EO-OFDM-IM) schemes. These approaches augment the spectral efficiency (SE) relative to classical counterparts by enlarging the index domain information using the so-called virtual sub-carriers. The classical O-OFDM-IM schemes do not necessarily enhance the SE because of low cardinality of IM complex-valued sub-carrier set which is limited by constraints like Hermitian symmetry. The index domain extension for EO-OFDM-IM schemes is achieved by replacing the complex-valued sub-carriers (as in O-OFDM-IM) by twice real-valued virtual sub-carriers. The realization of non-negative signals is based on precepts of classical O-OFDM approaches, that are direct current (DC) O-OFDM and asymmetrically clipped (AC) O-OFDM. Thus, we refer to the EO-OFDM-IM approaches as DCEO-OFDM-IM and ACEO-OFDM-IM. We shall establish that in addition to improving SE, EO-OFDM-IM schemes provide extended granularity effectuating better SE/energy efficiency (EE) trade-off and improved bit error rate performance over classical counterparts. The EO-OFDM-IM schemes, however, are suitable for lower alphabet cardinalities of pulse-amplitude modulation making it difficult to attain high spectral efficiencies while maintaining EE. To circumvent this limitation, dual-mode (DM) counterparts, DCEO-OFDM-DM and ACEO-OFDM-DM are proposed. The numerical simulations shall demonstrate that the EO-OFDM-DM approaches are more energy and spectral efficient than classical O-OFDM-DM schemes and provide an advantageous granularity for EE/SE trade-off. Additionally, we use efficient index mapping and de-mapping algorithms based on Pascal's triangle, which allows investigating these approaches for peak SE by precluding the so-called sub-block partitioning. For peak SE, the use of optimal maximum-likelihood (ML) detector is cumbersome, therefore, we introduce t

关键词： Optical-orthogonal frequency-division multiplexing index modulation intensity modulation and direct detection optical wireless systems

来源：评论

学校读者我要写书评

暂无评论

Optical spatial modulation design

引用

PHILOSOPHICAL TRANSACTIONS OF THE ROYAL SOCIETY A-MATHEMATICAL PHYSICAL AND ENGINEERING SCIENCES 2020年第2169期378卷 20190195-20190195页

作者： Cogalan, T. Haas, H. Panayirci, E. Univ Edinburgh Li Fi R&D Ctr Edinburgh EH9 3J1 Midlothian Scotland Kadir Has Univ Dept Elect & Elect Engn TR-34083 Istanbul Turkey

Visible light communication (VLC) systems are inherently signal-to-noise ratio (SNR) limited due to link budget constraints. One favourable method to overcome this limitation is to focus on the pre-log factors of the channel capacity. Multiple-input multiple-output (MIMO) techniques are therefore a promising avenue of research. However, inter-channel interference in MIMO limits the achievable capacity. Spatial modulation (SM) avoids this limitation. Furthermore, the performance of MIMO systems in VLC is limited by the similarities among spatial channels. This limitation becomes particularly severe in intensity modulation/direct detection (IM/DD) systems because of the lack of phase information. The motivation of this paper is to propose a system that results in a multi-channel transmission system that enables reliable multi-user optical MIMO SM transmission without the need for a precoder, power allocation algorithm or additional optics at the receiver. A general bit error performance model for the SM system is developed for an arbitrary number of light-emitting diodes (LEDs) in conjunction with pulse amplitude modulation. Based on this model, an LED array structure is designed to result in spatially separated multiple channels by manipulating the transmitter geometry. This article is part of the theme issue 'Optical wireless communication'.

关键词： light-fidelity multiple-input multiple-output spatial modulation intensity modulation and direct detection pulse amplitude modulation multi-user multiple-input multiple-output

来源：评论

学校读者我要写书评

暂无评论

Optical Wiretap Channel With Input-Dependent Gaussian Noise Under Peak- and Average-intensity Constraints

引用

IEEE TRANSACTIONS ON INFORMATION THEORY 2018年第10期64卷 6878-6893页

作者： Soltani, Morteza Rezki, Zouheir Univ Idaho Dept Elect & Comp Engn Moscow ID 83844 USA

This paper studies the optical wiretap channel with input-dependent Gaussian noise, in which the main distortion is caused by an additive Gaussian noise whose variance depends on the current signal strength. Subject to nonnegativity and peak-intensity constraints on the channel input, we first present a practical optical wireless communication scenario for which the considered wiretap channel is stochastically degraded. We then study the secrecy-capacity-achieving input distribution of this wiretap channel and prove it to be discrete with a finite number of mass points, one of them located at the origin. Moreover, we show that the entire rate-equivocation region of this wiretap channel is also obtained by discrete input distributions with a finite support. Similar to the case of the Gaussian wiretap channel under a peak-power constraint, here too, we observe that under nonnegativity and peak-intensity constraints, there is a tradeoff between the secrecy capacity and the capacity in the sense that both may not be achieved simultaneously. Furthermore, we prove the optimality of discrete input distributions in the presence of an additional average intensity constraint. Finally, we shed light on the asymptotic behavior of the secrecy capacity in the low-and high-intensity regimes. In the low-intensity regime, the secrecy capacity scales quadratically with the peak-intensity constraint. On the other hand, in the high-intensity regime, the secrecy capacity does not scale with the constraint.

关键词： Optical wiretap channel intensity modulation and direct detection peak- and average-intensity constraints low-intensity regime high-intensity regime input-dependent Gaussian noise

来源：评论

学校读者我要写书评

暂无评论

建议与咨询留下您的常用邮箱和电话号码，以便我们向您反馈解决方案和替代方法

时间限定

文献类型

馆藏选择

核心期刊

语言

文献类型

帮助

文字说明：

检索规则说明：

检索范例：

分类表

所选分类

限定检索结果

文献类型

馆藏范围

日期分布

学科分类号

主题

机构

作者

语言

请选择保存的检索档案：

请选择收藏分类：

通借通还

建议与咨询 留下您的常用邮箱和电话号码，以便我们向您反馈解决方案和替代方法

时间限定

文献类型

馆藏选择

核心期刊

语言

文献类型

帮助

文字说明：

检索规则说明：

检索范例：

分类表

所选分类

限定检索结果

文献类型

馆藏范围

日期分布

学科分类号

主题

机构

作者

语言

请选择保存的检索档案： 新增检索档案 确定 取消

请选择收藏分类： 新增自定义分类 确定 取消

通借通还

建议与咨询留下您的常用邮箱和电话号码，以便我们向您反馈解决方案和替代方法

请选择保存的检索档案：

请选择收藏分类：