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作者： sibghat ullah 北京邮电大学

学位级别：硕士

如今光接入网的流量发展趋势从简单的Web服务发展到多媒体服务和视频服务。在当前的流量快速增长趋势下,网络基础设施建设严重不足,这对光接入网的发展提出了更高的要求。波分复用无源光网络(WDM-PON)是下一代光接入网的有力备选方案。W... 详细信息

如今光接入网的流量发展趋势从简单的Web服务发展到多媒体服务和视频服务。在当前的流量快速增长趋势下,网络基础设施建设严重不足,这对光接入网的发展提出了更高的要求。波分复用无源光网络(WDM-PON)是下一代光接入网的有力备选方案。WDM-PON系统以其高带宽、低维护成本,及高传输能力而著称。WDM无源光网络的光线路终端(OLT)设计简单,成本低廉,非常适合下一代光接入网的发展。本文提出了一种基于光频梳(OFCG)的OLT架构方案,可用于WDM-PON系统和相干光通信。提出并实现了三种方案,可以在最少的资源利用率下产生光多载波。三种方案可以产生非常平坦的光多载波,而且具有高信噪比(TNR),多载波之间的幅度差(AD)最小。第一种是基于连续波(CW)激光源和单个Mach-Zehnder调制器(MZM),第二种方案使用级联结构的强度调制器(IMS)。第三种方案也是基于单个MZM,其中CW激光源被一个脉冲激光源所取代。通过仿真结果,可以看出所有的方案可以产生非常平坦的梳状线,具有高信噪比和最小幅度差,从而保证所提出方案可以在光通信网中进行部署。1)在WDM-PON系统中,首次采用了 1OGbps差分移相键控(DPSK)调制方案,并在25km标准单模光纤(SSMF)中传输33条梳状线。总体而言,330Gbps下行链路传输已经实现了最小的功率损耗。2)第二个多载波产生方案利用级联的强度调制器产生了非常优异的性能,产生的78个梳状线拥有具有高信噪比和较低幅度差。3)第三光多载波产生方案中采用单个MZM产生频率间隔,这与第一种方案相同,但可以产生更好的结果。该方案应用于WDM-PON的相干光通信中。在该方案中,利用1OGbps正交相移键控(QPSK)信号在20km SSMF上传输37个梳状线。利用相干光接收机进行信号接收和恢复。总而言之,用所提出的方案成功地实现了 740Gbps的下行链路传输,并且实现了最小的功率损耗。仿真结果表明了所提方案的有效性。

关键词：波分复用(WDM) 无源光网络(PON) 光频梳(OFC) 相干光通信

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Polarization-based optimal detection scheme for digital self-interference cancellation in full-duplex system

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The Journal of China Universities of Posts and Telecommunications 2020年第3期27卷 73-82页

作者： Adil Khan Zhang Jinling Muhammad Ayzed Mirza sibghat ullah Erum Ab basi Babar Hayat School of Electronic Engineering Beijing University of Posts and Telecom municationBeijing 100876China

In order to detect and cancel the self-interference(SI)signal from desired binary phase-shift keying(BPSK)signal,the polarization-based optimal detection(POD)scheme for cancellation of digital SI in a full-duplex(FD)system is *** POD scheme exploits the polarization domain to isolate the desired signal from the SI signal and then cancel the SI to obtain the interference-free desired signal at the *** FD communication,after antenna and analog cancellation,the receiver still contains residual SI due to non-linearities of hardware *** POD scheme,a likelihood ratio expression is obtained,which isolates and detects SI bits from the desired *** isolation of these signal points,the POD scheme cancels the residual *** compared to the conventional schemes,the proposed POD scheme gives significantly low bit error rate(BER),a clear constellation diagram to obtain the boundary between desired and SI signal points,and increases the receiver's SI cancellation performance in low signal to interference ratio(SIR)environment.

关键词： polarization full-duplex self-interference cancellation optimal detection

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Colorless WDM-PON Using Single Side Band Carrier Suppressed Signals Mitigating Carrier Rayleigh Backscattering

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China Communications 2016年第12期13卷 150-161页

作者： Rahat ullah Bo Liu Qi Zhang Yousaf Khan Amjad Ali Qinghua Tian Feng Tian M.Saad Khan Tabinda Salam sibghat ullah Lijia Zhang Xiangjun Xin State Key Laboratory of Information Photonics and Optical Communications Beijing University of Posts and TelecommunicationsNo.10 Xitucheng Road Beijing China 100876 School of Electronic Engineering Beijing University of Posts and Telecommunications No. 10 Xitucheng Road Beijing China 100876 Electrical Engineering Department Iqra University Peshawar Pakistan. Sarhad University Peshawar Pakistan 25000 School of Information and Communication Beijing University of Posts and TelecommunicationsNo. 10 Xitucheng Road Beijing China 100876

A new scheme is offered for minimizing carrier Rayleigh backscattering(CRB) in single feeder fiber based wavelength division multiplexed passive optical network(WDM-PON). The proposed scheme is based on single side band carrier suppressed(SSBCS) signal, both at network and receiver sides, used for the first time at optical line terminal(OLT) and optical network unit(ONU) sides. We use dual-drive Mach-zehnder modulator(DD-MZM) for generating SSB-CS signals, which decreases the expense per bit in full transmission. SSB-CS mitigates CRB, both at OLT and ONU sides, because of having no chance of reflections from the carrier. Since no extra dedicated RF or laser source is used at ONU side, we thus achieve cost effective colorless WDM-PON system. Suppressed signals from four channels, each of 10 Gbps, are multiplexed before injecting into the fiber span of 25 km at OLT. At ONU side, half of the downlink power is used for re-modulating the data signal. The simulation results show an errorfree transmission. Moreover, the detailed power budget calculations show that the proposed scheme can be sought out for splitting ratio up to 128. Hence it offers enough system's margin for unseen losses.

关键词： Carrier Rayleigh backscattering dual drive Mach-zehnder modulator single side band suppress carrier on-off keying

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Deep Learning-Based Trees Disease Recognition and Classification Using Hyperspectral Data

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Computers, Materials & Continua 2023年第10期77卷 681-697页

作者： Uzair Aslam Bhatti sibghat ullah Bazai Shumaila Hussain Shariqa Fakhar Chin Soon Ku Shah Marjan Por Lip Yee Liu Jing College of Information and Communication Engineering Hainan UniversityHaikou570228China Department of Computer Engineering Balochistan University of Information TechnologyEngineeringand Management Sciences(BUITEMS)QuettaPakistan Department of Computer Science Sardar Bahadur Khan Women’s UniversityQuettaPakistan Department of Computer Science Universiti Tunku Abdul RahmanKampar31900Malaysia Department of Software Engineering Balochistan University of Information TechnologyEngineeringand Management Sciences(BUITEMS)QuettaPakistan Faculty of Computer Science and Information Technology University of MalayaKuala Lumpur50603Malaysia

Crop diseases have a significant impact on plant growth and can lead to reduced *** methods of disease detection rely on the expertise of plant protection experts,which can be subjective and dependent on individual experience and *** address this,the use of digital image recognition technology and deep learning algorithms has emerged as a promising approach for automating plant disease *** this paper,we propose a novel approach that utilizes a convolutional neural network(CNN)model in conjunction with Inception v3 to identify plant leaf *** research focuses on developing a mobile application that leverages this mechanism to identify diseases in plants and provide recommendations for overcoming specific *** models were trained using a dataset consisting of 80,848 images representing 21 different plant leaves categorized into 60 distinct *** rigorous training and evaluation,the proposed system achieved an impressive accuracy rate of 99%.This mobile application serves as a convenient and valuable advisory tool,providing early detection and guidance in real agricultural *** significance of this research lies in its potential to revolutionize plant disease detection and management *** automating the identification process through deep learning algorithms,the proposed system eliminates the subjective nature of expert-based diagnosis and reduces dependence on individual *** integration of mobile technology further enhances accessibility and enables farmers and agricultural practitioners to swiftly and accurately identify diseases in their crops.

关键词： Plant disease Inception v3 CNN crop diseases

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Recent Developments in Authentication Schemes Used in Machine-Type Communication Devices in Machine-to-Machine Communication: Issues and Challenges

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Computers, Materials & Continua 2024年第4期79卷 93-115页

作者： Shafi ullah sibghat ullah Bazai Mohammad Imran Qazi Mudassar Ilyas Abid Mehmood Muhammad Asim Saleem Muhmmad Aasim Rafique Arsalan Haider Ilyas Khan Sajid Iqbal Yonis Gulzar Kauser Hameed Department of Computer Engineering Balochistan University of Information TechnologyEngineering and Management SciencesQuetta87300Pakistan Department of Information Technology Balochistan University of Information TechnologyEngineeringand Management SciencesQuetta87300Pakistan Department of Information Systems College of Computer Sciences and Information TechnologyKing Faisal UniversityHofuf in Al-Ahsa31982Saudi Arabia Department of Management Information Systems College of Business AdministrationKing Faisal UniversityHofuf in Al-Ahsa31982Saudi Arabia Department of Software Engineering College of ComputingRiphah International UniversityFaisalabad44000Pakistan Department of Electrical Engineering Balochistan University of Information Technology Engineeringand Management SciencesQuetta87300Pakistan Department of Mathematics College of Science Al-ZulfiMajmaah UniversityAl-Majmaah11952Saudi Arabia

Machine-to-machine (M2M) communication plays a fundamental role in autonomous IoT (Internet of Things)-based infrastructure, a vital part of the fourth industrial revolution. Machine-type communication devices(MTCDs) regularly share extensive data without human intervention while making all types of decisions. Thesedecisions may involve controlling sensitive ventilation systems maintaining uniform temperature, live heartbeatmonitoring, and several different alert systems. Many of these devices simultaneously share data to form anautomated system. The data shared between machine-type communication devices (MTCDs) is prone to risk dueto limited computational power, internal memory, and energy capacity. Therefore, securing the data and devicesbecomes challenging due to factors such as dynamic operational environments, remoteness, harsh conditions,and areas where human physical access is difficult. One of the crucial parts of securing MTCDs and data isauthentication, where each devicemust be verified before data transmission. SeveralM2Mauthentication schemeshave been proposed in the literature, however, the literature lacks a comprehensive overview of current M2Mauthentication techniques and the challenges associated with them. To utilize a suitable authentication schemefor specific scenarios, it is important to understand the challenges associated with it. Therefore, this article fillsthis gap by reviewing the state-of-the-art research on authentication schemes in MTCDs specifically concerningapplication categories, security provisions, and performance efficiency.

关键词： Authentication cyber security internet of things machine-type communication devices machine-to-machine communication

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