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Articles 1 - 30 of 1206

Full-Text Articles in Systems and Communications

Many Access For Small Packets Based On Precoding And Sparsity-Aware Recovery, Ronggui Xie, Huarui Yin, Xiaohui Chen, Zhengdao Wang Jan 2018

Many Access For Small Packets Based On Precoding And Sparsity-Aware Recovery, Ronggui Xie, Huarui Yin, Xiaohui Chen, Zhengdao Wang

Zhengdao Wang

Modern mobile terminals produce massive small data packets. For these short-length packets, it is inefficient to follow the current multiple access schemes to allocate transmission resources due to heavy signaling overhead. We propose a non-orthogonal many-access scheme that is well suited for the future communication systems equipped with many receive antennas. The system is modeled as having a block-sparsity pattern with unknown sparsity level (i.e., unknown number of transmitted messages). Block precoding is employed at each single-antenna transmitter to enable the simultaneous transmissions of many users. The number of simultaneously served active users is allowed to be even more ...


Degrees Of Freedom Region Of Wireless X Networks Based On Real Interference Alignment, Mahdi Zamanighomi, Zhengdao Wang Jan 2018

Degrees Of Freedom Region Of Wireless X Networks Based On Real Interference Alignment, Mahdi Zamanighomi, Zhengdao Wang

Zhengdao Wang

We first consider a single hop wireless X network with K transmitters and J receivers, all with a single antenna. Each transmitter conveys an independent message for each receiver. The channel is assumed to have constant coefficients. We develop an interference alignment scheme for this setup and derive an achievable degrees of freedom (DoF) region. We show that in some cases, the derived region meets a previous outer bound, and hence, is the (exact) DoF region. For our achievability schemes, we divide each message into streams and use real interference alignment on the streams. Several previous results on the DoF ...


Big Data And Parkinson’S Disease: Exploration, Analyses, And Data Challenges, Mahalakshmi Senthilarumugamveilukandammal, Sree Nilakanta, Baskar Ganapathysubramanian, Vellareddy Anantharam, Anumantha Kanthasamy, Auriel A. Willette Jan 2018

Big Data And Parkinson’S Disease: Exploration, Analyses, And Data Challenges, Mahalakshmi Senthilarumugamveilukandammal, Sree Nilakanta, Baskar Ganapathysubramanian, Vellareddy Anantharam, Anumantha Kanthasamy, Auriel A. Willette

Mechanical Engineering Conference Presentations, Papers, and Proceedings

In healthcare, a tremendous amount of clinical and laboratory tests, imaging, prescription and medication data are being collected. Big data analytics on these data aim at early detection of disease which will help in developing preventive measures and in improving patient care. Parkinson disease is the second-most common neurodegenerative disorder in the United States. To find a cure for Parkinson's disease biological, clinical and behavioral data of different cohorts are collected, managed and propagated through Parkinson’s Progression Markers Initiative (PPMI). Applying big data technology to this data will lead to the identification of the potential biomarkers of Parkinson ...


Variance-Optimal Offline And Streaming Stratified Random Sampling, Trong Duc Nguyen, Ming-Hung Shih, At&T Labs–Research, Srikanta Tirthapura, Bojian Xu Jan 2018

Variance-Optimal Offline And Streaming Stratified Random Sampling, Trong Duc Nguyen, Ming-Hung Shih, At&T Labs–Research, Srikanta Tirthapura, Bojian Xu

Electrical and Computer Engineering Publications

Stratified random sampling (SRS) is a fundamental sampling technique that provides accurate estimates for aggregate queries using a small size sample, and has been used widely for approximate query processing. A key question in SRS is how to partition a target sample size among different strata. While Neyman's allocation provides a solution that minimizes the variance of an estimate using this sample, it works under the assumption that each stratum is abundant, i.e. has a large number of data points to choose from. This assumption may not hold in general: one or more strata may be bounded, and ...


Femtosecond Laser Micromachining Of Low-Temperature Co-Fired Ceramic And Glass Fiber Reinforced Polymer Printed Circuit Boards Materials, Raif Farkouh Dec 2017

Femtosecond Laser Micromachining Of Low-Temperature Co-Fired Ceramic And Glass Fiber Reinforced Polymer Printed Circuit Boards Materials, Raif Farkouh

Theses, Dissertations, and Student Research from Electrical & Computer Engineering

Low-temperature co-fired ceramic (LTCC), and glass fiber reinforced polymer (GFRP) printed circuit boards (PCBs) are two materials used for the packaging of electronics. The excellent mechanical and electrical properties of LTCC, combined with the ability to embed passive components offer superior radio frequency (RF) performance and device miniaturization for high-frequency applications. Due to its unique properties, LTCC provides superior performance in applications as diverse as military radar, imaging systems, advanced automotive sensing, telecommunications, and satellites. The use of LTCC in these applications has created a demand for the micromachining of holes, channels, and cavities with specific geometries and structures. Likewise ...


Queue Stability Analysis In Network Coded Wireless Multicast., Nadieh Mohamadi-Moghadam Dec 2017

Queue Stability Analysis In Network Coded Wireless Multicast., Nadieh Mohamadi-Moghadam

Electronic Theses and Dissertations

In this dissertation queue stability in wireless multicast networks with packet erasure channels is studied. Our focus is on optimizing packet scheduling so as to maximize throughput. Specifically, new queuing strategies consisting of several sub-queues are introduced, where all newly arrived packets are first stored in the main sub-queue on a first-come-first-served basis. Using the receiver feedback, the transmitter combines packets from different sub-queues for transmission. Our objective is to maximize the input rate under the queue stability constraints. Two packet scheduling and encoding algorithms have been developed. First, the optimization problem is formulated as a linear programming (LP) problem ...


Design And Simulation Of An 8-Bit Successive Approximation Register Charge-Redistribution Analog-To-Digital Converter, Sumit K. Verma Nov 2017

Design And Simulation Of An 8-Bit Successive Approximation Register Charge-Redistribution Analog-To-Digital Converter, Sumit K. Verma

Electrical Engineering Theses

The thesis initially investigates the history of the monolithic ADCs. The next chapter explores the different types of ADCs available in the market today. Next, the operation of a 4-bit SAR ADC has been studied. Based on this analysis, an 8-bit charge-redistribution SAR ADC has been designed and simulated with Multisim (National Instruments, Austin, TX). The design is divided into different blocks which are individually implemented and tested. Level-1 SPICE MOSFET models representative of 5μm devices were used wherever individual MOSFETs were used in the design. Finally, the power dissipation during the conversion period was also estimated. The supply voltage ...


Ka-Band Vivaldi Antenna With Novel Core Element For High-Gain, Manh Ha Hoang, Kansheng Yang, Matthias John, Patrick Mcevoy, Max Ammann Nov 2017

Ka-Band Vivaldi Antenna With Novel Core Element For High-Gain, Manh Ha Hoang, Kansheng Yang, Matthias John, Patrick Mcevoy, Max Ammann

Conference Papers

A high gain Vivaldi antenna employing an integrated core element is proposed. The maximum antenna gain is 16.9 dBi and it performs better than 14 dBi over the complete Ka (24 - 40 GHz) band. The design methodology, excitation arrangement and field distribution features are described.


Crowdsourced Smart Cities, Robert A. Iannucci, Anthony Rowe Oct 2017

Crowdsourced Smart Cities, Robert A. Iannucci, Anthony Rowe

Bob Iannucci

The vision of applying computing and communication technologies to enhance life in our cities is fundamentally appealing. Pervasive sensing and computing can alert us to imminent dangers, particularly with respect to the movement of vehicles and pedestrians in and around crowded streets. Signaling systems can integrate knowledge of city-scale traffic congestion. Self-driving vehicles can borrow from and contribute to a city-scale information collaborative. Achieving this vision will require significant coordination among the creators of sensors, actuators, and application-level software systems. Cities will invest in such smart infrastructure if and only if they are convinced that the value can be realized ...


2017 Eclipse Rfd-900 Still Image System, Tristan Running Crane, Uciel Garcia Olmedo, David Schwehr Oct 2017

2017 Eclipse Rfd-900 Still Image System, Tristan Running Crane, Uciel Garcia Olmedo, David Schwehr

2017 Academic High Altitude Conference

As part of the NASA Space Grant 2017 Eclipse Ballooning Project, Montana Space Grant Consortium designed a camera system capable of transmitting still images from a balloon borne payload to a remote ground station via a RFD-900 radio. This payload consists of a Raspberry Pi, a Raspberry Pi camera, custom power supply and a RFD 900MHz radio. This system was designed to record pictures at high and low resolution at altitude. The low resolution images could be selected for downlinking back to the ground via the radio, while the high resolution pictures were saved to the Raspberry Pi memory card ...


University Of Maine High Altitude Ballooning Eclipse Experience, Kent Seneres, Derek Haas, William Bessette, Richard Eason Oct 2017

University Of Maine High Altitude Ballooning Eclipse Experience, Kent Seneres, Derek Haas, William Bessette, Richard Eason

2017 Academic High Altitude Conference

The University of Maine High Altitude Ballooning (UMHAB) team launched two balloons during the August 21, 2017 total solar eclipse, producing a consistent online video stream of the eclipse to an altitude of 110,000 feet. This paper discusses the key factors that lead to a successful launch and recovery, such as thorough testing procedures, redesign of components, choice of launch site, and a touch of luck. In preparation for the event, the team tested the equipment and code over eleven balloon launches. Airplane based testing and land testing were conducted for the tracking and video stream components. The payloads ...


Footprintid: Indoor Pedestrian Identification Through Ambient Structural Vibration Sensing, Shijia Pan, Tong Yu, Mostafa Mirshekari, Jonathon Fagert, Amelie Bonde, Ole J. Mengshoel, Hae Young Noh, Pei Zhang Sep 2017

Footprintid: Indoor Pedestrian Identification Through Ambient Structural Vibration Sensing, Shijia Pan, Tong Yu, Mostafa Mirshekari, Jonathon Fagert, Amelie Bonde, Ole J. Mengshoel, Hae Young Noh, Pei Zhang

Ole J Mengshoel

We present FootprintID, an indoor pedestrian identification system that utilizes footstep-induced structural vibration to infer pedestrian identities for enabling various smart building applications. Previous studies have explored other sensing methods, including vision-, RF-, mobile-, and acoustic-based methods. They often require specific sensing conditions, including line-of-sight, high sensor density, and carrying wearable devices. Vibration-based methods, on the other hand, provide easy-to-install sparse sensing and utilize gait to distinguish different individuals. However, the challenge for these methods is that the signals are sensitive to the gait variations caused by different walking speeds and the floor variations caused by structural heterogeneity.

We present ...


Improving Speech Recognition For Interviews With Both Clean And Telephone Speech, Sung Woo Choi Sep 2017

Improving Speech Recognition For Interviews With Both Clean And Telephone Speech, Sung Woo Choi

Journal of Undergraduate Research at Minnesota State University, Mankato

High quality automatic speech recognition (ASR) depends on the context of the speech. Cleanly recorded speech has better results than speech recorded over telephone lines. In telephone speech, the signal is band-pass filtered which limits frequencies available for computation. Consequently, the transmitted speech signal may be distorted by noise, causing higher word error rates (WER). The main goal of this research project is to examine approaches to improve recognition of telephone speech while maintaining or improving results for clean speech in mixed telephone-clean speech recordings, by reducing mismatches between the test data and the available models. The test data includes ...


Information Theoretic Study Of Gaussian Graphical Models And Their Applications, Ali Moharrer Aug 2017

Information Theoretic Study Of Gaussian Graphical Models And Their Applications, Ali Moharrer

LSU Doctoral Dissertations

In many problems we are dealing with characterizing a behavior of a complex stochastic system or its response to a set of particular inputs. Such problems span over several topics such as machine learning, complex networks, e.g., social or communication networks; biology, etc. Probabilistic graphical models (PGMs) are powerful tools that offer a compact modeling of complex systems. They are designed to capture the random behavior, i.e., the joint distribution of the system to the best possible accuracy. Our goal is to study certain algebraic and topological properties of a special class of graphical models, known as Gaussian ...


Distributed Emitter Detector Design Under Imperfect Communication Channel, Soumyadip Patra Aug 2017

Distributed Emitter Detector Design Under Imperfect Communication Channel, Soumyadip Patra

University of New Orleans Theses and Dissertations

We consider the distributed detection of an emitter using multiple sensors deployed at deterministic locations. The signal from the emitter follows a signal attenuation model dependent on the distance between the sensor and the emitter. The sensors transmit their decisions to the fusion center through a parallel access Binary Symmetric Channel (BSC) with a cross-over probability. We seek to optimize the detection performance under a prescribed false alarm at the sensor level and at the system level. We consider the triangular topology structure and using the least favorable emitter range study the impact of the BSC on the system level ...


Gui For Mri-Compatible Neural Stimulator And Recorder, Soo Han Soon, Nishant Babaria, Ranajay Mandal, Zhongming Liu Aug 2017

Gui For Mri-Compatible Neural Stimulator And Recorder, Soo Han Soon, Nishant Babaria, Ranajay Mandal, Zhongming Liu

The Summer Undergraduate Research Fellowship (SURF) Symposium

Functional magnetic resonance imaging (fMRI) and electroencephalography (EEG) are useful tools to analyze brain activities given active stimulation. However, the electromagnetic noise from the MRI distorts the brain signal recording and damages the subject with excessive heat generated on the electrodes attached to the skin. MRI-compatible recording and stimulation systems previously developed at LIBI lab were capable of removing the electromagnetic noise during the imaging process. Previously, the hardware systems had required the integrative software that could control both circuits simultaneously and enable users to easily change recording and stimulation parameters. Graphical user interface (GUI) programmed with computer language informed ...


Ocean Wind Speed Measurement Using Wideband Gnss-R Signals, Brandon J. Kozel, Han Zhang, James L. Garrison, Benjamin Nold Aug 2017

Ocean Wind Speed Measurement Using Wideband Gnss-R Signals, Brandon J. Kozel, Han Zhang, James L. Garrison, Benjamin Nold

The Summer Undergraduate Research Fellowship (SURF) Symposium

The use of Global Navigation Satellite System-Reflectometry (GNSS-R) for remote sensing of ocean wind speeds has been explored for nearly two decades and has become an important passive remote sensing technique for verification of hurricane formation models. To obtain wind speed measurements, reflected GNSS signals are first cross-correlated with locally generated copies to construct delay-doppler maps (DDMs). Through statistical models, DDMs can provide information about the mean-square slope (MSS) of the ocean surface, which is related to wind speed. Previous studies have focused on legacy signals such as GPS L1. However, it is expected that the MSS relationship with ocean ...


Two Senior Projects: 2.4 Ghz, 40% Efficiency Radio Frequency Amplifier, Ieee Design Contest, & Design And Implementation Of A Software Costas Loop For Audio Frequencies, Robert J. Tong Aug 2017

Two Senior Projects: 2.4 Ghz, 40% Efficiency Radio Frequency Amplifier, Ieee Design Contest, & Design And Implementation Of A Software Costas Loop For Audio Frequencies, Robert J. Tong

Electrical Engineering

How to Read this Document:

This document combines two senior project reports. The first senior project documents designing a class AB RF amplifier. The second, discusses the design and implementation of a software Costas loop for audio frequencies. The first report begins on the next page, while the Costas loop report starts on page 24. The two reports are orthogonal from one another. It is not a prerequisite to read the RF amplifier report before reading the Costas loop report. This document is merely two reports combined into one document. The second report, about the Costas loop, was written as ...


Application-Aware Cognitive Multi-Hop Wireless Networking Testbed And Experiments, Trenton T. Evans Jul 2017

Application-Aware Cognitive Multi-Hop Wireless Networking Testbed And Experiments, Trenton T. Evans

Theses, Dissertations, and Student Research from Electrical & Computer Engineering

In this thesis, we present a new architecture for application-aware cognitive multihop wireless networks (AC-MWN) with testbed implementations and experiments. Cognitive radio is a technique to adaptively use the spectrum so that the resource can be used more efficiently in a low cost way. Multihop wireless networks can be deployed quickly and flexibly without a fixed infrastructure. In presented new architecture, we study backbone routing schemes with network cognition, routing scheme with network coding and spectrum adaptation. A testbed is implemented to test the schemes for AC-MWN. In addition to basic measurements, we implement a video streaming application based on ...


Software-Defined Networking Enabled Resource Management And Security Provisioning In 5g Heterogeneous Networks, Xiaoyu Duan Jul 2017

Software-Defined Networking Enabled Resource Management And Security Provisioning In 5g Heterogeneous Networks, Xiaoyu Duan

Electronic Thesis and Dissertation Repository

Due to the explosive growth of mobile data traffic and the shortage of spectral resources, 5G networks are envisioned to have a densified heterogeneous network (HetNet) architecture, combining multiple radio access technologies (multi-RATs) into a single holistic network. The co-existing of multi-tier architectures bring new challenges, especially on resource management and security provisioning, due to the lack of common interface and consistent policy across HetNets. In this thesis, we aim to address the technical challenges of data traffic management, coordinated spectrum sharing and security provisioning in 5G HetNets through the introduction of a programmable management platform based on Software-defined networking ...


Towards Continuous And Passive Authentication Across Mobile Devices: An Empirical Study, Xiao Wang, Tong Yu, Ole J. Mengshoel, Patrick Tague Jul 2017

Towards Continuous And Passive Authentication Across Mobile Devices: An Empirical Study, Xiao Wang, Tong Yu, Ole J. Mengshoel, Patrick Tague

Ole J Mengshoel

Mobile devices, such as smartphones and tablets, have become prevalent given their ample functionality brought by a variety of applications. Unfortunately, these devices face security and privacy threats due to unauthorized access. Ordinary protection mechanisms such as passcode and fingerprint verification are widely employed to mitigate the threats. To achieve strong security without sacrificing usability, extensive research efforts have been devoted to continuous authentication through passive sensing and behavior modeling. Nowadays, more and more users own multiple devices. This trend presents opportunities for further optimization of authentication across devices. In this paper, we conduct an empirical study on how a ...


Wireless Positioning And Tracking For Internet Of Things In Gps-Denied Environments, Bekir Sait Ciftler Jun 2017

Wireless Positioning And Tracking For Internet Of Things In Gps-Denied Environments, Bekir Sait Ciftler

FIU Electronic Theses and Dissertations

Wireless positioning and tracking have long been a critical technology for various applications such as indoor/outdoor navigation, surveillance, tracking of assets and employees, and guided tours, among others. Proliferation of Internet of Things (IoT) devices, the evolution of smart cities, and vulnerabilities of traditional localization technologies to cyber-attacks such as jamming and spoofing of GPS necessitate development of novel radio frequency (RF) localization and tracking technologies that are accurate, energy-efficient, robust, scalable, non-invasive and secure. The main challenges that are considered in this research work are obtaining fundamental limits of localization accuracy using received signal strength (RSS) information with ...


Mobility Analysis And Management For Heterogeneous Networks, Karthik Vasudeva Jun 2017

Mobility Analysis And Management For Heterogeneous Networks, Karthik Vasudeva

FIU Electronic Theses and Dissertations

The global mobile data traffic has increased tremendously in the last decade due to the technological advancement in smartphones. Their endless usage and bandwidth-intensive applications will saturate current 4G technologies and has motivated the need for concrete research in order to sustain the mounting data traffic demand. In this regard, the network densification has shown to be a promising direction to cope with the capacity demands in future 5G wireless networks. The basic idea is to deploy several low power radio access nodes called small cells closer to the users on the existing large radio foot print of macrocells, and ...


Analysis Of Various Classification Techniques For Computer Aided Detection System Of Pulmonary Nodules In Ct, Barath Narayanan Narayanan, Russell C. Hardie, Temesguen Messay Jun 2017

Analysis Of Various Classification Techniques For Computer Aided Detection System Of Pulmonary Nodules In Ct, Barath Narayanan Narayanan, Russell C. Hardie, Temesguen Messay

Russell C. Hardie

Lung cancer is the leading cause of cancer death in the United States. It usually exhibits its presence with the formation of pulmonary nodules. Nodules are round or oval-shaped growth present in the lung. Computed Tomography (CT) scans are used by radiologists to detect such nodules. Computer Aided Detection (CAD) of such nodules would aid in providing a second opinion to the radiologists and would be of valuable help in lung cancer screening. In this research, we study various feature selection methods for the CAD system framework proposed in FlyerScan. Algorithmic steps of FlyerScan include (i) local contrast enhancement (ii ...


Degrees Of Freedom Region For An Interference Network With General Message Demands, Lei Ke, Aditya Ramamoorthy, Zhengdao Wang, Huarui Yin Jun 2017

Degrees Of Freedom Region For An Interference Network With General Message Demands, Lei Ke, Aditya Ramamoorthy, Zhengdao Wang, Huarui Yin

Zhengdao Wang

We consider a single hop interference network with K transmitters, each with an independent message and J receivers, all having the same number (M) of antennas. Each receiver requests an arbitrary subset of the messages. This generalizes the well-known K user M antenna interference channel, where each message is requested by a unique receiver. For this setup, we derive the exact degrees of freedom (DoF) region. Our achievability scheme generalizes the interference alignment scheme proposed by Cadambe and Jafar '08. In particular, we achieve general points in the DoF region by using multiple base vectors and aligning the interference at ...


Differential Tilt Variance Effects Of Turbulence In Imagery: Comparing Simulation With Theory, Daniel A. Lemaster, Russell C. Hardie, Szymon Gladysz, Matthew D. Howard, Michael Armand Rucci, Matthew E. Trippel, Jonathan D. Power, Barry K. Karch Jun 2017

Differential Tilt Variance Effects Of Turbulence In Imagery: Comparing Simulation With Theory, Daniel A. Lemaster, Russell C. Hardie, Szymon Gladysz, Matthew D. Howard, Michael Armand Rucci, Matthew E. Trippel, Jonathan D. Power, Barry K. Karch

Russell C. Hardie

Differential tilt variance is a useful metric for interpreting the distorting effects of turbulence in incoherent imaging systems. In this paper, we compare the theoretical model of differential tilt variance to simulations. Simulation is based on a Monte Carlo wave optics approach with split step propagation. Results show that the simulation closely matches theory. The results also show that care must be taken when selecting a method to estimate tilts.


Efficient Macromodeling And Fast Transient Simulation Of High Speed Distributed Interconnects, Sadia Wahid Jun 2017

Efficient Macromodeling And Fast Transient Simulation Of High Speed Distributed Interconnects, Sadia Wahid

Electronic Thesis and Dissertation Repository

In the first part of the thesis, an efficient macromodeling technique based on Loewner Matrix (LM) approach has been presented to model multi-port distributed systems using tabulated noisy data. In the proposed method, Loewner Model data from previous rational approximation are used to create less noisy eigenvectors in an iterative manner. As a result, the biasing effect of the LM model approximated by the noisy data is reduced. It is illustrated that this method improves the accuracy of the Loewner Matrix modeling for noisy frequency data.

In the second part, a fast and robust algorithm is introduced for time-domain simulation ...


Recursive Robust Pca Or Recursive Sparse Recovery In Large But Structured Noise, Chenlu Qiu, Namrata Vaswani, Brian Lois, Leslie Hogben Jun 2017

Recursive Robust Pca Or Recursive Sparse Recovery In Large But Structured Noise, Chenlu Qiu, Namrata Vaswani, Brian Lois, Leslie Hogben

Namrata Vaswani

This paper studies the recursive robust principal components analysis problem. If the outlier is the signal-of-interest, this problem can be interpreted as one of recursively recovering a time sequence of sparse vectors, St, in the presence of large but structured noise, Lt. The structure that we assume on Lt is that Lt is dense and lies in a low-dimensional subspace that is either fixed or changes slowly enough. A key application where this problem occurs is in video surveillance where the goal is to separate a slowly changing background (Lt) from moving foreground objects (St) on-the-fly. To solve the above ...


Capturing Cognitive Fingerprints From Keystroke Dynamics, J. Morris Chang, Chi-Chen Fang, Kuan-Hsing Ho, Norene Kelly, Pei-Yuan Wu, Yixiao Ding, Chris Chu, Stephen B. Gilbert, Amed E. Kamal, Sun-Yuan Kung Jun 2017

Capturing Cognitive Fingerprints From Keystroke Dynamics, J. Morris Chang, Chi-Chen Fang, Kuan-Hsing Ho, Norene Kelly, Pei-Yuan Wu, Yixiao Ding, Chris Chu, Stephen B. Gilbert, Amed E. Kamal, Sun-Yuan Kung

Morris Chang

Conventional authentication systems identify a user only at the entry point. Keystroke dynamics can continuously authenticate users by their typing rhythms without extra devices. This article presents a new feature called cognitive typing rhythm (CTR) to continuously verify the identities of computer users. Two machine techniques, SVM and KRR, have been developed for the system. The best results from experiments conducted with 1,977 users show a false-rejection rate of 0.7 percent and a false-acceptance rate of 5.5 percent. CTR therefore constitutes a cognitive fingerprint for continuous. Its effectiveness has been verified through a large-scale dataset. This article ...


Impact Of Threshold Clipping On Bit Error Rate In Ofdm-Like Systems, Felipe Hoshino, Theodore Grosch Jun 2017

Impact Of Threshold Clipping On Bit Error Rate In Ofdm-Like Systems, Felipe Hoshino, Theodore Grosch

The Kennesaw Journal of Undergraduate Research

In wireless communications, 3GPP LTE is one of the solutions to meet the greater transmission data rate demand. One issue inherent to this technology is the PAPR (Peak-to-Average Power Ratio) of OFDM (Orthogonal Frequency Division Multiplexing) modulation. This high PAPR affects of the efficiency of power amplifiers. One approach to mitigate this effect is the Crest Factor Reduction (CFR) technique. In this work we simulate the impact of Hard Limited Clipping Crest Factor Reduction technique on BER (Bit Error Rate) in OFDM based Systems. In general, the results showed CFR has more effect on higher digital modulation schemes, as expected ...