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2016 - 20196
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Subject: Electronics and Communication Engineering ×

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Now showing 1 - 6 of 6
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    ThesisItemOpen Access
    STUDY AND PERFORMANCE EVALUATION OF QUASI AND ROTATED QUASI ORTHOGONAL SPACE TIME BLOCK CODED MIMO SYSTEMS WITH ADVANCE DETECTOR SCHEME UNDER VARIOUS MODULATION TECHNIQUES
    (DEPARTMENT OF ELECTRONICS & COMMUNICATION ENGINEERING VAUGH INSTITUTE OF AGRICULTURAL ENGINEERING AND TECHNOLOGY SAM HIGGINBOTTOM UNIVERSITY OF AGRICULTURE, TECHNOLOGY AND SCIENCES PRAYAGRAJ (FORMERLY ALLAHABAD, 2019) MISHRA, PRIYANKA; SHUKLA, Prof. (Dr.) CHANDRA KANT
    The current progress in wireless communication system boost the throughput over wireless channels, thereby increasing the reliability, high data rate, high efficiency, mobility, and accessibility. In this thesis, it is surveyed on combining the spatial multiplexing and space-time coding techniques under Rayleigh fading channel in MIMO wireless communication systems architecture. Providing different rates, capacity, diversities, and performance. It is analysed the decoding algorithms like Maximum Likelihood decoding, V-BLAST, Sphere Decoder technique and also analysed its performance with different Orthogonal Space-Time Block Codes, like Alamouti Space-Time Block Codes, quasi-orthogonal space-time block codes and rotated quasi-orthogonal space-time block codes. The objective of this thesis is based on the detailed analysis of the combination of spatial multiplexing and space time coding techniques under Rayleigh fading channel constraint in MIMO wireless communication systems is presented. The decoding algorithms of V-BLAST and Sphere Decoder are analyzed and their performance is evaluated using different Orthogonal Space-Time Block Codes techniques, with quasi and rotated quasi-orthogonal space-time block codes. The BER vs SNR curves of all the proposed algorithms have been verified for all modulation schemes including 64 QAM, 16 QAM, QPSK and BPSK. A modified k and k1 Sphere decoder are proposed for the significant reduction of BER at higher modulation schemes. The BER for proposed k sphere decoder is 0.01% as compared to the conventional sphere decoder whose BER is 0.1%. Thus, 90% decrement in BER is achieved by applying k sphere decoder. Similarly, for k1 sphere decoder is 0.001% which means further 90% decrement in BER is obtained while applying k1 sphere decoder. BER for 64 QAM modulation is calculated at optimum SNR of 20 dB and it has been shown that BER gets significantly reduced by applying proposed decoding algorithms.BER for the conventional sphere decoder is 0.001, for k sphere decoder is 0.0001 and for k1 sphere decoder is 0.00001.The proposed sphere decoders with such a low BER and low complexity can be used in equalizer circuits for 4G and 5G next generation communication system
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    ThesisItemOpen Access
    SECURE AND EFFICIENT ROUTE TRUST AND REPUTATION MANAGEMENT SYSTEMS FOR GENERIC AD HOC NETWORKS
    (Department of Electronics and Communication Engineering Faculty of Engineering and Technology SAM HIGGINBOTTOM UNIVERSITYOF AGRICULTURE TECHNOLOGY AND SCIENCES NAINI, PRAYAGRAJ-211007, 2019) ASAYH, SAMEER MUFTAH; Paulus, Dr. Rajeev
    Trust is the main feature of mobile ad hoc networks (MANETs). It enables entities to cope with uncertainty and uncontrollability caused by the free will of others. Trust Aware Routing Framework (TARF) can be developed into a complete and independent routing protocol; the purpose is to allow existing routing protocols to incorporate the implementation of TARF with the least effort and thus producing a secure and efficient route trust fully-functional protocol and the reputation management in ad hoc networks. Unlike other security measures, TARF requires neither tight time synchronization nor known geographic information. Most importantly, TARF proves resilient under various attacks exploiting the replay of routing information, which is not achieved by previous security protocols. Even under strong attacks such as sinkhole attacks, wormhole attacks as well as sybil attacks, and hostile mobile network condition, TARF demonstrates steady improvement in network performance. This prevents the direct application of techniques suited for other networks. An adversary can exploit this defect to launch various harmful or even devastating attacks against the routing protocols, including sinkhole attacks, wormhole attacks and sybil attacks. Without tight time synchronization or known geographic information, TARF provides trustworthy. Finally, a TARF module with low overhead can be integrated into existing routing protocols with ease. Security and trust are fundamental challenges when it comes to the deployment of large wireless sensor networks. In this thesis, the propose a novel hierarchical trust management scheme that minimizes communication and storage overheads. The scheme takes into account direct and indirect (group) trust in trust evaluation as well as the energy associated with sensor nodes in service selection. It also considers the dynamic aspect of trust by introducing a trust varying function which could give greater weight to the most recently obtained trust values in the trust calculation. Although there are a large number of researches on secure routing in mobile ad hoc networks, only a few consider the anonymous communication. In thesis, the define more strict requirements on the inscrutability and security properties of the various protocol, and notice that earlier works only provide weak localization based and mobile node traveling routes are discernible, and are vulnerable to specific attacks. Even though there are members of protocols which stresses on security of routing, no satisfying throughputs have been attained, most of the existing protocol are not strongly guarded against the ambush of counterfeit packets or denial of service. Therefore, in this thesis proposed the modified onion 5 routing protocol is presented, which concentrates on the defense against attack. This proposed protocol is termed as authenticated secure routing, i.e. Identity, confidentiality and geo- locality and ensure the place of safety to bare routes against various passive and active attacks. The intend to design a routing protocol which can protect the privacy of nodes and routes, and at the same time ensure the security of discovered routes. The purpose of this system is to motivate the participating nodes not only to help each other relaying data traffic, but also identify the median nodes, and to truncate them for the period of the route founding and increasing the route‘s security and reliability. Hence, an anonymous and secure route path can be established. Additionally, it has better characteristic for defending the modified onion routing protocol improves the performance and efficiency through our simulation
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    ThesisItemOpen Access
    DESIGN ANALYSIS OF SHORTING PIN MICROSTRIP PATCH ANTENNA FOR C-BAND APPLICATION
    (Department of Electronics and Communication Engineering (SIET),SHUATS-Allahabad,U.P., 2018) SINGH, RAKESH KUMAR; Kumar, Dr. Anil
    In this work, a multi frequency microstrip antenna (MSA) for wireless applications is designed. The proposed MSA comprised of elliptical patch antenna with shorting pin. This antenna is fed by coaxial probe. The design parameters are major and minor axis of elliptical patch, the position of shorting pin and feeding point of probe are mentioned in table-1. The proposed antenna can provide optimized multi frequency by varying the above design parameters. FR-4 substrate with dielectric constant 4.4 is chosen. The multi frequencies are 4.49 GHz, and 6.69GHz, which covers the applications such as satellite communications, for full-time satellite TV networks. And for the second case, the work is as a novel design of a Pentagonal shaped patch antenna is presented for ultra wideband wireless communication applications. Designed Microstrip patch antenna consists of a pentagonal patch which is found to resonant at frequency 4.8571 GHz, with return loss -19.65 dB having satisfactory radiation properties. The proposed antenna is a compact design of 30mm × 20mm area on the FR4-epoxy substrate with dielectric constant of 4.4 and thickness of 1.8 mm. The designed antenna structure with 3.45 dB gain is planar, simple and compact hence it can be easily embedded for wireless communication systems and integrated with microwave circuitry for low manufacturing cost.
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    ThesisItemOpen Access
    THEORETICAL CHARACTERIZATION OF NOVEL HIGH ELECTRON MOBILITY TRANSISTOR AND FinFET
    (Department of Electronics and Communication Engineering Shepherd Institute of Engineering and Technology (SHUATS) Allahabad, U.P., 2018) PANDEY, KAMAL PRAKASH; Kumar, Dr. Anil
    A GaN High electron mobility transistors (HEMTs) have been designed and simulated for high voltage and high speed applications. Simple AlGaN/GaN on sapphire substrates HEMT and HEMT with oxide layer have been proposed for achieving high current carrying capability as well as high speed switching capability and analyzed using ATLAS (Silvaco) simulator. The device characteristics suggest that the MOS-HEMT has better performance compared to the conventional HEMT. Advantages of HEMT on the basis of band gap, electron mobility, saturation drift velocity and power handling capacity has also been discussed. Simulation result shows the effect of temperature on the cut off frequency, for temperature 248 K the technology 90 nm has the cut off frequency of 24.1 GHz while for the same technology at higher temperature of 373 K the cut off frequency decrease to 9 GHz. It is designed and simulated of a single gate FinFET structure on the SOI substrate using Silvaco TCAD. A 45 nm channel length FinFET structure is compared with conventional MOSFET structure having same channel length. Different structural and process parameters such as length, width, height, dielectric thickness, doping etc has been optimized for designing the FinFET. The simulated structure shows the threshold voltage of 0.37643; lower DIBL, higher drain saturation current and improved parameters as compared to the conventional MOSFET structure.
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    ThesisItemOpen Access
    AN EFFICIENT AND SECURE TRANSMISSION OF SOLITON FOR WDM SYSTEMS
    (DEPARTMENT OF ELECTRONICS AND COMMUNICATION ENGINEERING SHEPHERD INSTITUTE OF ENGINEERING AND TECHNOLOGY SAM HIGGINBOTTOM UNIVERSITY OF AGRICULTURE TECHNOLOGY AND SCIENCES ALLAHABAD-211007, 2018) ANTWIWAA, ANITA; KUMAR, Dr. ANIL
    The information hunger of the world is increasing tremendously with time and it is compelling telecommunication companies to mount up strategies to meet the high data demand as well as providing an efficient service to their clients. Amidst the exponential growth of information hungry customers, telecommunication companies dream of providing quality of services at a lower cost to their users in order to survive the competition in the market. Transmitting multiples of signals through a single channel in view of serving millions of customers simultaneously by wavelength division multiplexing (WDM) is the answer. Four-wave mixing (FWM) is the optical signal drift from one channel to the other. This effect has the tendency of imposing a threat on the fiber communication network thereby undermining the security and confidentiality of the information sent by the customers. This work will study the soliton system by analysis of the various impairments in the soliton WDM channel using Matlab software. The results obtained show that when the phase of solitons are varied with equal amplitude and a constant spacing, the solitons interacts and join combines to form one pulse. They walk through each other and separates after travelling for some time. This affirms that soliton pulses are stable even in the mist of interaction when travelling under the right conditions. When the amplitude is varied keeping the phase and separation constant shows an increased in the amplitude due to an increase in the interaction rate thereby reducing the efficiency and QoS of the soliton signals. Moreover, varying the separation of the soliton pulses has effect on the transmission. When soliton pulses are kept so tight in the channel, perturbation will occur therefore the closer the pulse separation the greater the interaction rate and vice versa. Spacing between iii soliton pulses in close proximity should be equal to or more than the width of the pulse so as to overcome interactions. FWM effect and its security issues will be analyzed. The various Matlab simulation results of this FWM will be studied using optisystem software. The obtained results shows that FWM effect can reduce the signal strength by 60% and also broadening the spectrum of the pulse and these are all alarming factors. The evolution of new pulses due to FWM effect also consumes bandwidth which makes data transmission expensive to telecommunication companies. Furthermore, two forms of WDM system attacks will be considered. These attacks include a clone source based attack where the adversary tries to replicate the transmitted signal of the legitimate user by transmitting at the same wavelength and power and the different wavelength source based attack where the adversary transmit at a wavelength different from that of the legitimate user thereby creating interaction effects igniting security issues. These two novel attacks were studied using optisystem software. The outcome of these attacks show that WDM source based attack has a great impact on WDM signals. In the presence of channel impairments, the signals suffers from various non-linearity issues which degenerates into various security issues. The clone source based attack adversely affects the security of a WDM system since the adversary operates with the same wavelength and power of the legitimate user. The DWSBA also causes the signals to be affected by non-linearity effects like pulse broadening and FWM which creates room for security vulnerabilities in WDM. Finally, a proposed Secured WDM system will be designed to mitigate the various security issues using optisystem software. A multiple stage encryption with phase detection and frequency grating network has been proposed to secure the WDM network from intrusion activities. The phase detection method plays a checking role on the transmitted data by comparing the phase of the iv signal received with the phase of the transmitted signal and correcting the resultant phase received. Since the phase of the transmitted signal is known, it is easy to detect whether there has been an intrusion activities on the network. This takes care of the clone source based attack because the phase detection method can determine the exact signal transmitted by the user. The presence of the frequency grating filter plays an august role in the detection and separation of DWSBA by separating the various frequencies received at the output. The output obtained shows that the phase detection method with frequency grating filtering method work together to detect and correct all these channel impairments and attacks makes the proposed WDM phase detection model the most stable and secured WDM system.
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    ItemOpen Access
    Design and Analysis of Ultra Wide Band MIMO Antennas for Wireless Communications
    (Sam Higginbottom Institute of Agriculture, Technology & Sciences (SHIATS), 2016) Srivastava, Garima; Paulus, Rajeev
    Ultra Wide Band (UWB) technology is rapidly developing area in the field of Wireless Communication. There are many challenges in this field, one of the challenge is to design an antenna which covers the entire UWB frequency range, the another challenge is to design an UWB Multiple input-Multiple output antenna which will increase the channel capacity and will allow several users to access the various services at the same time. The objective of this thesis is to design UWB antennas that operates in the frequency range from 3.1 to 10.6 GHz and has band notched characteristics. Another objective is to design UWB MIMO antenna and UWB MIMO antennas with band notched characteristics. The thesis starts with designing and implementing UWB antennas with discussions covering their operation, electrical behavior and performance. UWB antennas are designed and analyzed using microstrip feeding technique and coaxial feed to achieve low profile and compatibility with Printed Circuit Board. Also, Different techniques for obtaining a bandstop function in the 5 to 6 GHz frequency band to avoid interference with other existing worldwide interportability for microwave access (WIMAX) systems are numerically and experimentally presented. In Communication systems, Multiple Input–Multiple Output (MIMO) technology, which involves the use of multiple antennas at both the transmitter and receiver, is used to significantly enhance the data transmission performance and channel capacity. Antennas for this system are designed, to ensure that isolation between elements should be less than - 15 dB. Thus, Antennas are typically placed apart from others at least half wavelength of the lowest operating frequency, and this could lead to increase in dimensions of MIMO antenna. Therefore, miniaturizing the antenna size and improving the isolation coefficients are the two most important aims for MIMO antennas. An Ultra Wide Band (UWB) multiple Page ii input and multiple output (MIMO) antenna having shared radiator with dual band rejection characteristics is designed and analyzed. The proposed antenna is based on the concept of dual polarization. The antenna consists of two tapered Co-planer Waveguide (CPW) feeds printed on one side of the substrate and a circular shared radiator on the other side. The radiator is shared between two antenna elements. High isolation between the antenna elements is achieved by introducing a rectangular slot in the circular radiator and an inverted Y shaped stub on the ground plane at an angle of 45°. The designed antenna rejects the WiMAX and WLAN band of frequencies by employing Elliptical Split Ring Slots (ESRS) in the shared radiator. The diversity performance of UWB MIMO antenna is also studied. The antenna is fabricated on FR4 substrate and has a small size of 41 mm × 41 mm. The simulated and measured results are in good agreement which demonstrate its potential use in UWB portable devices. The challenge of multipath fading in Ultra Wide Band technology is removed with another MIMO antenna in the thesis. The high isolation among the antenna elements is a basic requirement for good diversity performance. To cope up with this challenge a uniplanar UWB MIMO antenna is designed and analyzed. This antenna can also be used for Wireless Personal Area Network (WPAN), Wireless Body Area Network (WBAN). It has single common circular radiator for both the antenna elements.