Thumbnail Image

Theses

Browse

2016 - 201932
Reset filters
Subject: Electronics and Communication Engineering × End date: 2019 × Start date: 2016 ×
Reset filters

Search Results

Now showing 1 - 9 of 32
  • Thumbnail Image
    ThesisItemOpen Access
    Channel prediction in cognitive radio network using hierarchical neural system for throughput maximization
    (G.B. Pant University of Agriculture and Technology, Pantnagar - 263145 (Uttarakhand), 2019-09) Goyal, Neetu; Mathur, Sanjay
    Wireless Communication has shown exponential upsurge in demand of wireless devices. Due to ever increasing demand of wireless communication, there is spectrum scarcity which is caused by a fixed spectrum allocation policy. Studies on usage pattern reveal that most of the allocated spectrum experiences low utilization under fixed spectrum allocation regime and spectrum occupancy varies from milliseconds to hours. This motivated the concept of frequency reuse that would allow secondary networks to borrow unused radio spectrum from primary licensed networks (users). The core technology behind frequency reuse is Cognitive Radio for which one of the essential components is channel sensing, i.e., the wireless devices can sense the radio spectrum environment within their operating range to detect frequency bands that are not occupied by primary users. This thesis presents a study on maximizing the throughput for secondary user by predicting the primary free channel in advance to save time in sensing and maximizing transmission time in a frame. The study involves exhaustive exploration of various classifiers for predictive decision making and later development of hierarchal neural network model for predicting best possible channel for transmission in following frame. It starts with performance analysis of spectrum sensing techniques, energy detector and matched filter are discussed with simulation results. On the basis of these results, energy detector is found best technique which is further analysed in fading scenario and with mobile SU. There exists a sensing-throughput trade off, hence proposed model focuses on parallel processing for predicting the next channel while primary user continues to transmit in current frame. The model considers three type of radio channel condition scenario namely, constant fading, cyclostationary fading and fast fading. The performance of the system is found to be closer to upper bound for best channel throughput and results are discussed in comparison to lower bound statistics.
  • Thumbnail Image
    ThesisItemOpen Access
    Design and development of band notched antenna with DGS for UWB applications
    (G.B. Pant University of Agriculture and Technology, Pantnagar - 263145 (Uttarakhand), 2019-09) Sharma, Himanshu; Paras
    In the present day scenario the need for wireless communication is increasing in order to support more users and to provide more information with higher data rate. Ultra wideband is a wireless technology used for high speed data transfer over short distances. But in the ultra wideband frequency band there are some other frequency bands like WLAN, WiMAX, C band, X band etc. which may cause interference with the ultra wideband . Therefore notching technique is used in order to remove the interfering band from the ultra wideband range. In the proposed work a dual band-notched antenna with DGS for ultra wideband applications is designed and fabricated. Size of the proposed antenna is 36 x 33 x 1.6 mm3 and FR-4 is used as the substrate for the proposed antenna. Antenna is resonating in the frequency range of 2.5-12.5 GHz with peak gain of 5.47 dBi giving total bandwidth of 10 GHz. Antenna is having two band notches from 3-4 GHz and 6.95-7.8 GHz removing the WiMAX and XSCS band from the ultra wideband range. Simulation of the antenna is done in HFSS and fabrication of the antenna is done using PCB designing machine. Testing of the antenna is done using vector network analyser (VNA).
  • Thumbnail Image
    ThesisItemOpen Access
    Blind equalization of bipolar 2-PAM and 4-QAM signals using non-linear autoregressive exogenous input neural system
    (G.B. Pant University of Agriculture and Technology, Pantnagar - 263145 (Uttarakhand), 2019-08) Singh, Vipra; Mathur, Sanjay
    This thesis presents a study on the blind equalization of Bipolar 2-PAM and 4-QAM signals using Non-Linear Autoregressive Exogenous Input (NARX) neural system. The thesis can be divided into two parts, the first part involves the theoretical issues about the blind equalization and neural equalizers, the second part addresses the problem of software implementation. The thesis begins with some basic concepts and theories of the channel equalization, which are fundamentals for designing blind equalizers, and then introduces blind equalization concept. Next presented in the thesis is the neural network architecture that is suitable for blind equalization. Its stability and convergence properties are analyzed in the thesis. Also, the thesis proposes a blind equalization model that combines the concept of decision-feedback equalizer and the NARX neural networks. Simulations with 2-PAM and 4-QAM signals have been carried out to test the performances of the proposed model. The second part of the thesis presents a software equalizer design which has been simulated. Based on the results from the simulation, the performance of the neural equalizer is discussed. Finally, some suggestions for further work are included at the end of the thesis.
  • Thumbnail Image
    ThesisItemOpen Access
    Controllable notched edge tapered rectangular patch antenna using U-slot line feed and DGS for UWB applications
    (G.B. Pant University of Agriculture and Technology, Pantnagar - 263145 (Uttarakhand), 2019-08) Sharma, Sunil; Paras
    Antenna is an extremely indispensible part of wireless communication systems. As the requirements of wireless devices increasing day by day like Bluetooth devices, radio frequency devices and size of such devices decreasing accordingly. To meet the requirement of small size devices, antenna need to be compact and single antenna can be used for several wireless applications, without affecting the antenna parameters. Therefore the concept of ultra-wideband is used. The defected ground structure and slotting is used to enhance the performance of antenna. Proposed antenna is designed in the substrate size of 35×30 with height of 1.6mm. FR-4 epoxy substrate having permittivity of 4.4 and loss tangent of .02 is used. Ground size is reduced to obtain monopole antenna and slots are cut on both patch as well as ground plane to improve the performance of antenna in terms of bandwidth and gain. Proposed antenna is simulated using Ansoft HFSS software, fabricated in PCB designing machine and tested using VNA. Proposed antenna resonates in 3.1-14.45GHz band with notched frequency bands from 3.31-3.6GHz (WiMAX) and 4.4-5.8GHz (WLAN) with the bandwidth of 11.35 GHz having gain above 2.17dB and efficiency 80-90% throughout the entire frequency range. Proposed antenna has applications in UWB frequency range with no interference for WiMAX and WLAN band in wireless communication.
  • Thumbnail Image
    ThesisItemOpen Access
    Compact broadband microstrip antenna with DGS for wireless applications
    (G.B. Pant University of Agriculture and Technology, Pantnagar - 263145 (Uttarakhand), 2019-08) Pant, Bharat; Gangwar, R.P.S.
    With the rapid growth of wireless communications in recent years, users need multiple frequency bands at the same time to access different services such as voice video and data. Therefore, it has become to have compact microstrip antenna (MSA) with a wide band to avoid employing multiple antennas to fulfil requirement of the users. The MSA is a revolution in the field of wireless applications due to its low cost, ease of installation, performance and low profile structure which make it a high quality contender. for many communication equipment. The main objective of this proposed work is to develop a compact broadband microstrip antenna with DGS for wireless applications in the frequency range of 2-7 GHz. The proposed antenna is designed using TLM model and is simulated and optimized using HFSSv.15 with a centre frequency of 4GHz. Proposed antenna is used to operate at the frequency range of 2.73-6.50 GHz in wireless applications like WiMAX (3.6 GHz), Hi-LAN (5.15-5.35 GHz), WLAN IEEE802a (5.2 GHZ), and DSRC for a car to car communication (5.850-5.925 GHz). A 6-6.50 GHz might be used for future 5G communication and other application as CCTV, Camera and Cmax. The proposed antenna is fabricated on a FR4 substrate having thickness 1.6 mm and loss tangent of 0.02. The fabricated antenna has dimensions 32×22×1.6 mm3which makes it compact in nature. The parameters in terms of reflection coefficient and VSWR for the proposed antenna (fabricated) are measured and compared with the simulated ones, which show good agreement. The proposed antenna is also compared with the earlier designed antennas. The measured broad bandwidth with reflection coefficient below -10 dB is found to be 4500 MHz in the frequency range from 2.70- 7.2 GHz. Simulated peak gain of 5.22 dBi and radiation efficiency of 90-98% for the proposed antenna in the frequency range from 2.73 - 6.50 GHz are observed. The proposed antenna has a stable radiation pattern in both E and H planes.
  • Thumbnail Image
    ThesisItemOpen Access
    A triangular patch monopole antenna with DGS ground having CSRR based controllable notch characteristics for UWB applications
    (G.B. Pant University of Agriculture and Technology, Pantnagar - 263145 (Uttarakhand), 2019-08) Upreti, Mitesh; Paras
    Monopole configuration and DGS in antenna is used to achieve a high bandwidthUWB antenna (3.1-10.6 GHz) with acceptable gain. The main concern of UWB antenna is that they are sensitive towards electromagnetic interferences with existing narrowband wireless communication systems, so it is necessary to design antennas with multiband filtering characteristics to avoid interferences. Therefore, it is necessary to design the UWB antenna with band notched characteristics to reduce the complexity and make cost effective systems. The proposed work consists of a triangular patch antenna monopole antenna having dual band notch characteristics for the UWB applications. The size of the antenna is 24×28×1.6 mm3.Dielectric substrate used is FR4 epoxy having dielectric constant εr = 4.4 and loss tangenttan 𝛿 = 0.02. The variant of proposed antenna is also designed to confirm the controllability feature of CSRR notch. The proposed antenna resonates in the UWB range from 3.1 to 11 GHz and peak gain of 7 dB at 10.84 GHz (Proposed Antenna). The dual notch band characteristics due to inverted U slot and CSRR is obtained from 4.9 to 5.36 GHz to 6.1 to 6.78 GHz for the proposed antenna. The variant of proposed antenna shows the shifting of CSRR notch from 6.1 to 6.78 GHz to 7.2 to 7.8 GHz by reducing the size of CSRR by 0.5 mm. The geometric parameters of inverted U slot & CSRRs are chosen to eliminate interference with the WLAN/Future mobile communications or X band.
  • Thumbnail Image
    ThesisItemOpen Access
    Design of low power and high speed sense amplifier based Flip-Flop in 90nm CMOS technology
    (G.B. Pant University of Agriculture and Technology, Pantnagar - 263145 (Uttarakhand), 2019-08) Pandey, Kailash; Tomar, Abhishek
    With the increasing processor speed demand of peripheral devices of high speed and low power consumption has grown. Power consumption in the circuits can be reduced by decreasing capacitance at the high impedance nodes along with the reduction in the number of transistors. So flip-flops are used which is the main building block in designing the digital circuits that creates a larger impact on circuits speed and power consumption. Performance of flip-flop also determines the performance of the whole synchronous circuit. sense amplifier based flip-flops which are a type of master-slave flip-flop are designed having a simple design of slave latch, less clock skew and nearly zero set-up time. The proposed designs achieve a reduction in power by the use of the method of conditional precharging. The slave latch designs minimize the latency of the circuit. The designs show improvement in PDP. These design works for different ranges of voltages which exhibits the robustness and suitability of the circuits. Cadence Virtuoso 90nm CMOS technology tool is used for the simulations. In comparison to various SAFF studied the proposed designs show more than 26.27% and 31.72% improvement in delay and power respectively.
  • Thumbnail Image
    ThesisItemOpen Access
    Design of low power inverter based OTA in FinFET technology
    (G.B. Pant University of Agriculture and Technology, Pantnagar - 263145 (Uttarakhand), 2019-02) Mohit Kumar; Sharma, K.K.
    OTA performance analysed by following four different analysis on SPICE tool First DC analysis of proposed circuit is done on input sweep from -0.7 to 0.7 to understand the output current behaviour and finding proper operating point. The following parameter has been calculated as – Output current swing from -125μV to 125μV, differential mode transconductance 215.29 μS at IDS = 23 μA and total power consumption at Z=50Ω is 234μW. VG1 and VG4 terminal voltage can be used to tune the transconducatance value. There is no need of extra regulated on chip supply voltage. Second, Frequency response analysis is performed to calculate differential mode gain , common mode gain, unity gain bandwidth, phase margin, CMRR, PSRR. Achieved open loop gain of the circuit is 52dB , unity gain bandwidth is 1Ghz at CL = 0.1pF , phase margin is 80˚,PSRR+ obtained 52.007dB, PSRR- obtained 52.012dB, CMRR obtained 49.5dB. Positive slew rate and negative slew rate values are 1.034 v/ns and 0.83 v/ns respectively In proposed circuit noise analysis has been done at load Z=50Ω. Proposed circuit suffer with total input noise value of 1.08μV/√Hz and total output noise calculated to be 6.43nV/√Hz .
  • Thumbnail Image
    ThesisItemOpen Access
    Simulation study of dual edge triggered static flip flop in FinFET technology
    (G.B. Pant University of Agriculture and Technology, Pantnagar - 263145 (Uttarakhand), 2019-02) Dinesh Kumar; Sharma, K.K.
    The current very large scale integration technology (VLSI) based on bulk MOSFETs has approached the scaling limits, due to increased leakage and short channel effects (SCEs). Fin field effect transistors (FinFETs) is a promising alternative for addressing the challenges posed by continued scaling and allowing further scaling. Fabrication of FinFETs is compatible with that of conventional CMOS, thus making possible the very rapid deployment to manufacturing. Flip-flop is main building block in digital circuits that have large impact on circuit speed and power consumption. Performance of flip-flop determines the performance of whole synchronous circuit. Switching activity of a circuit node is a main concern to reduce dynamic power. Dynamic power is directly proportional to switching activity. Switching activity can vary according to input data thereby for different input data pattern different power dissipation can occur. Dual edge triggering is an effective way to reduce the power consumption, it can reduce switching activity for same data throughout. In this thesis, different existing dual edge triggered static flip-flop have been studied and their performances have been evaluated using CMOS and FinFET technology. All these circuits have been simulated with the help of HSPICE simulator. 32nm CMOS technology is used for MOSFET based flip-flop and Berkeley predictive technology model (BPTM) is used for 32nm CMOS and FinFET based dual edge triggered flipflops. Simulation results of CMOS based flip-flops are then compared with the simulation result of FinFET based flip-flops. Parameters considered for the comparison are power consumption, delay and power delay product. With the help of simulation results it is observed that FinFET improved all the parameters of dual edge triggered flip-flops.