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Reconfigurable Array Control Via Convolutional Neural Networks, Garrett A. Harris
Reconfigurable Array Control Via Convolutional Neural Networks, Garrett A. Harris
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A method for the beam forming control of an array of reconfigurable antennas is presented. The method consists of using two parallel convolutional neural networks (CNNs) to analyze a desired radiation pattern image, or mask, and provide a suggestion for the reconfigurable element state, array shape, and steering weights necessary to obtain the radiation pattern. This research compares beam forming systems designed for three distinct element types: a patch antenna, a reconfigurable square spiral antenna restricted to a single reconfigurable state, and the fully reconfigurable square spiral. The parametric sweeps for the design of the CNNs are presented along with …
Amygdala Modeling With Context And Motivation Using Spiking Neural Networks For Robotics Applications, Matthew Aaron Zeglen
Amygdala Modeling With Context And Motivation Using Spiking Neural Networks For Robotics Applications, Matthew Aaron Zeglen
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Cognitive capabilities for robotic applications are furthered by developing an artificial amygdala that mimics biology. The amygdala portion of the brain is commonly understood to control mood and behavior based upon sensory inputs, motivation, and context. This research builds upon prior work in creating artificial intelligence for robotics which focused on mood-generated actions. However, recent amygdala research suggests a void in greater functionality. This work developed a computational model of an amygdala, integrated this model into a robot model, and developed a comprehensive integration of the robot for simulation, and live embodiment. The developed amygdala, instantiated in the Nengo Brain …
Fault-Tolerant Control Of Autonomous Ground Vehicle Under Actuator And Sensor, Vaishnavi Janakiraman
Fault-Tolerant Control Of Autonomous Ground Vehicle Under Actuator And Sensor, Vaishnavi Janakiraman
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Unmanned ground vehicles have a wide range of potential applications including autonomous driving, military surveillance, emergency responses, and agricultural robotics, etc. Since such autonomous vehicles need to operate reliably at all times, despite the possible occurrence of faulty behaviors in some system components, the development of fault-tolerant control schemes is a crucial step in ensuring reliable and safe operations. In this research, a fault-tolerant control scheme is developed for a nonlinear ground vehicle model with possible occurrence of both actuator faults in the form of loss of effectiveness (LOE) and sensor bias faults. Based on the vehicle and fault models …
The Theory And Design Of Class E Power Amplifiers For Impulse Excitation In Nuclear Magnetic Resonance, Owen D. Riemer
The Theory And Design Of Class E Power Amplifiers For Impulse Excitation In Nuclear Magnetic Resonance, Owen D. Riemer
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A new method for analyzing the effectiveness of NMR impulse power amplifiers was developed using a classical linear systems approach to NMR. The method demonstrates a way to compare NMR power amplifiers and outputs. Thermodynamic calculations and the harmonic content of NMR amplifiers is presented to provide a complete description of the NMR power amplifier design problem. A design procedure for class E NMR power amplifiers with a pi-impedance matching network is outlined for matching the amplifier to the transmitter coil. The thesis concludes with the presentation of a 53 MHz power amplifier developed with the procedure. The complete amplifier …
Interferometry Analysis Method For Colliding Plasma Generated With Exploded Wires, Michael D. Gruesbeck
Interferometry Analysis Method For Colliding Plasma Generated With Exploded Wires, Michael D. Gruesbeck
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Building upon recent work to estimate electron and ion densities from paired interferograms, the current work develops a model for the 2D interference phase function. Unlike the previous work that only estimated a radial plasma profile from images of a singly exploded straight Cu wire, we estimate 2D properties from a colliding plasma generated from two simultaneously exploded wires. First, a 2D phase model is proposed for the interference patterns of the images taken at 1064 nm and 532 nm. Then, the model parameters are estimated using Fourier analysis. Secondly, the plasma region in each image is partitioned into subregions …
Hardware Security And Side Channel Power Analysis For 16x16 Booth Multiplier In 65nm Cmos Technology, Kanchan Vissamsetty
Hardware Security And Side Channel Power Analysis For 16x16 Booth Multiplier In 65nm Cmos Technology, Kanchan Vissamsetty
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As feature size is scaling down, dynamic power consumption reduces but static power consumption increases. Due to the increase of static power, leakage currents as a source, the information can be exploited successfully as a side-channel to recover the secrets of the cryptographic implementations. An attacker who has access to the hardware fabrication can insert a Trojan to the design to steal or alter information. In this thesis, a post-fab static voltage variation/detection technique is developed to detect the potential fabrication process Trojan insertion. The technique is, dividing the designed circuit into N equal segments, where each segment would have …
Reconfigurable Antenna Array Using The Pin-Diode-Switched Printed Square Spiral Element, Corey M. Stamper
Reconfigurable Antenna Array Using The Pin-Diode-Switched Printed Square Spiral Element, Corey M. Stamper
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A dual-band array of reconfigurable elements is modeled and simulated. The array consists of four single square spiral microstrip antennas that are corporately fed and are used as a unit cell. The single square spiral uses two PIN diodes as switching elements to achieve reconfiguration. The array has four switch states that can operate over four discrete frequencies in the S and C bands. The unit cell radiation pattern is used with the pattern multiplication model to quickly simulate the array pattern of larger arrays. A 3 x 3 array of the unit cells is modeled with only the center …
Design And Simulation Of Boost Dc - Dc Pulse Width Modulator (Pwm) Feed-Forward Control Converter, Calenia L. Franklin
Design And Simulation Of Boost Dc - Dc Pulse Width Modulator (Pwm) Feed-Forward Control Converter, Calenia L. Franklin
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Military aircraft systems’ power losses are occurring during the loading operations; loading and unloading causes the aircraft systems to lose power. The primary aircraft power source is provided by a 400Hz Ground Power Units (GPU). This GPU provides power to interior lighting, the aircraft cargo compartment, and other electrical systems (i.e. bus). The issues are during loading and unloading on the aircraft, which causes dropout of aircraft power supplied by the external 400Hz GPU. The majority of the military aircraft require a high voltage and a high current with a 270V power output. This thesis analyzes using Feed-Forward PWM Boost …
Mitigating Atmospheric Phase Errors In Sal Data, Randy S. Depoy Jr.
Mitigating Atmospheric Phase Errors In Sal Data, Randy S. Depoy Jr.
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Synthetic aperture ladar (SAL) is an emerging remote sensing technology capable of providing high-resolution, interpretable, and timely imagery. SAL and synthetic aperture radar (SAR) are similar in that they provide high-resolution imagery suitable for a wide-variety of applications beyond the diffraction limit of the real aperture. Several advantages of SAL are; realistic imagery resulting from diffuse scattering of optically-rough objects, fine directionality of laser beam making the technology inherently low probability-of-detect, and shorter synthetic aperture collection times, all of which result from operating at optical as opposed to RF wavelengths. With the dramatic decrease in wavelength, SAL systems become more …
Comparing Rf Fingerprinting Performance Of Hobbyist And Commercial-Grade Sdrs, Travis R. Smith
Comparing Rf Fingerprinting Performance Of Hobbyist And Commercial-Grade Sdrs, Travis R. Smith
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Radio Frequency Fingerprinting (RFF) research typically uses expensive, laboratory grade receivers which have high dynamic range, very stable oscillators, large instantaneous bandwidth, multi-rate sampling, etc. In this study, the RFF effectiveness of lower grade receivers is considered. Using software-defined radios (SDRs) of different cost and performance, a linear regression model is developed to predict RFF performance. Unlike two previous studies of SDR effectiveness that used commercial and lab-grade SDRs, the experiment here focused on hobbyist and commercial-grade SDRs (RTL-SDR, B200-mini, N210). A regression model is proposed for a generic SDR. Using a full-factorial experiment matrix, the gain, sample rate, and …
The Steady-State Analysis Of The Non-Isolated And Isolated Type Sepic Pwm Dc-Dc Converters For Ccm, Anuroop Reddy Dasari
The Steady-State Analysis Of The Non-Isolated And Isolated Type Sepic Pwm Dc-Dc Converters For Ccm, Anuroop Reddy Dasari
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The purpose of this thesis is to develop the theory for analysing and designing the non-isolated and isolated type of SEPIC converters for continuous conduction mode (CCM). The non-isolated converter has single output. The isolated converter considered has two cases: single output and multi-output. The principle of operation of each circuit is explained during different time intervals of the switching cycle. The analytical expressions for various characteristics of the circuits are derived, such as: MV DC and MIDC of the lossless and lossy converter; average and peak-to-peak currents through the inductors, primary and secondary windings of the transformer; average and …
Logistic Function Based Nonlinear Modeling And Circuit Analysis Of The Bipolar Vacancy Migration Memristor, Isaac P. Abraham
Logistic Function Based Nonlinear Modeling And Circuit Analysis Of The Bipolar Vacancy Migration Memristor, Isaac P. Abraham
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Memristor is an acronym for memory resistor. Memristors promise to be building blocks for high density memory and analog computation. Hewlett Packard’s announcement in 2008 of having fabricated a memristor on an integrated circuit scale has created a tangible excitement in this field. Understanding and exploiting the full potential of these devices requires good compact models. Symbolic modeling provides a balance between achieving accurate empirical fit and generating closed form expressions. This dissertation simplifies the transport equation into a variable coefficient advection equation, very similar to a Burgers’ equation traditionally used in fluid dynamics. The Burgers’-like model reveals the dual …
Analytical Approach To Multi-Objective Joint Inference Control For Fixed Wing Unmanned Aerial Vehicles, Julian L. Casey
Analytical Approach To Multi-Objective Joint Inference Control For Fixed Wing Unmanned Aerial Vehicles, Julian L. Casey
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Fixed-wing Unmanned Aerial Vehicles (UAVs) have been found highly useful in various environments, including military and law enforcement. With the increased use of fixed-wing UAVs, there becomes an increased need to optimize the resources available. One approach to resource management is to create multi-objective flights. This thesis presents the design, analysis, and experimental implementation of multi-objective resource management for the resource of Range, distance available to the UAV, from the viewpoint of Intelligence Surveillance and Reconnaissance (ISR). First, a Simulation Environment is created capable of tracking multiple fixed-wing UAVs and to allow for the UAVs’ being controlled by an externally …
Online Clustering With Bayesian Nonparametrics, Matthew D. Scherreik
Online Clustering With Bayesian Nonparametrics, Matthew D. Scherreik
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Clustering algorithms, such as Gaussian mixture models and K-means, often require the number of clusters to be specified a priori. Bayesian nonparametric (BNP) methods avoid this problem by specifying a prior distribution over the cluster assignments that allows the number of clusters to be inferred from the data. This can be especially useful for online clustering tasks, where data arrives in a continuous stream and the number of clusters may dynamically change over time. Classical BNP priors often overestimate the number of clusters, however, leading researchers to develop new priors with more control over this tendency. To date, BNP algorithms …
Tapped-Inductor Buck Dc-Dc Converter, Ankit Chadha
Tapped-Inductor Buck Dc-Dc Converter, Ankit Chadha
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There is a high demand for low step-down dc voltage conversions. Many conventional power converters that are currently being used have a moderate conversion ratio and this may not be sufficient to meet the demand. This can be achieved by either cascading power converters or using converters with a low step-down conversion ratio. Cascading the converters increases the power conversion stage complexity and increase the order of the system, while also affecting the stability. Using converters with a high conversion ratio seems to be a more intelligent option to root. This dissertation tackles to analyze one such converter, called tapped-inductor …
High Security Cognitive Radio Network Via Instantaneous Channel Information, Kaiyu Huang
High Security Cognitive Radio Network Via Instantaneous Channel Information, Kaiyu Huang
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The cognitive radio network has been considered one of the most promising communication technologies for next generation wireless communication. One important aspect of cognitive radio network research is the so-called Primary User Authentication. Naturally, the primary user authentication in the cognitive radio network requires strong encryption. For the primary user identification, this dissertation provides a method which hides the user information in the header of the data frames with an underlay waveform. It is important to note that the underlay waveform will not bring redundancy data to the communication system. Using the synchronizing frequency as the underlay waveform carrier also …
Digital Instantaneous Frequency Measurement Receiver For Fine Frequency And High Sensitivity, Bilal Khudhur Abdulhammed Abdulhamed
Digital Instantaneous Frequency Measurement Receiver For Fine Frequency And High Sensitivity, Bilal Khudhur Abdulhammed Abdulhamed
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Wideband technology has been applied to many wide bandwidth applications when there is a need to send much different information in a short time from one point and received from another point in high precision and accuracy. A wideband receiver reports a signal without tuning if the signal is within the input bandwidth. The analog Instantaneous Frequency Measurement (IFM) receiver has been used for decades to cover a very wide input bandwidth and report one accurate frequency on a short pulse at a time. The digital IFM use a high sampling rate ADC to operate in a wide bandwidth, Hilbert …
Fault-Tolerant Mapping And Localization For Quadrotor Uav, Maximillian Andrew Gilson
Fault-Tolerant Mapping And Localization For Quadrotor Uav, Maximillian Andrew Gilson
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This research aims to accomplish three main tasks for a quadrotor UAV with mapping and navigation capabilities. Firstly, a Simultaneous Localization and Mapping (SLAM) system is developed utilizing a laser rangefinder an open source SLAM algorithm called GMapping. This system allows for mapping of the surrounding environment as well as localizing the position of the quadrotor, enabling position control. Secondly, several path planning algorithms were implemented and evaluated. This allows the quadrotor to navigate through the environment even in the presence of obstacles. Lastly, to compensate for possible faults in the SLAM measurements, a fault-tolerant control method is developed. Real-time …
Multifunctional Oxide Heterostructures For Next-Generation Tunable Rf/Microwave Electronics, Hyung Min Jeon
Multifunctional Oxide Heterostructures For Next-Generation Tunable Rf/Microwave Electronics, Hyung Min Jeon
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Recent advanced radio frequency (RF) microwave device demands for low power consumption, light weight, compact package, and high performance. To achieve the high performance, applying magnetic materials is becoming indispensable in many of those devices. Thus, the role of magnetism in those devices is important high-quality magnetic materials not only improves the performance of microwave devices but also opens opportunities in developing novel concepts of devices utilizing spin wave excitation, non-reciprocal wave propagation, and the electromagnetic coupling in multiferroic materials. Among all the others, manipulating magnetic properties in multiferroic material started a couple years ago. Multiferroic materials are a group …
Design Of An Ultra-Wideband Microstrip Antenna Array With Low Size, Weight And Power, Paul Staffan
Design Of An Ultra-Wideband Microstrip Antenna Array With Low Size, Weight And Power, Paul Staffan
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This study focuses on the use of microstrip antenna technology for designing an ultra-wideband antenna to meet low size, weight and power requirements. Based on the recent literature for such antennas, a quasi-log periodic microstrip antenna array is designed to operate from 8 to 40 GHz (radar bands X, Ku, K and Ka). The array consists of 33 co-linear, inset-fed, square patches on a Roger’s Duroid substrate, and is modeled using the Advanced Design System software from Keysight. The simulated results show the antenna has pass-band gains greater than 5 dB, a half-power beamwidth of 30 degrees, and linear polarization …
Stability Analysis Of Leg Configurations For Bipedal Running, Nitin Jaiswal
Stability Analysis Of Leg Configurations For Bipedal Running, Nitin Jaiswal
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A legged robot with three-segmented limbs is used to study the effects of leg compliance originating from the joint level on the stability of hopping in place and running. The three-segments allow each leg to be kinematically configured an infinite number ways that satisfy the desired landing condition parameters, total leg length and angle. These two parameters along with the amount of energy thrust during stance determine the motion of the system during a single stride. The goal of this work is to explore the potential values for the leg parameters of three-segment leg, that provide additional stability when compared …
A Low-Area, Energy-Efficient 64-Bit Reconfigurable Carry Select Modified Tree-Based Adder For Media Signal Processing, Priscilla Sharon Allwin
A Low-Area, Energy-Efficient 64-Bit Reconfigurable Carry Select Modified Tree-Based Adder For Media Signal Processing, Priscilla Sharon Allwin
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Multimedia systems play an essential part in our daily lives and have drastically improved the quality of life over time. Multimedia devices like cellphones, radios, televisions, and computers require low-area and low-power reconfigurable adders to process greedy computation algorithms for the real-time audio/video signal and image processing such as discrete cosine transform, inverse discrete cosine transform, and fast Fourier transform, etc. In this thesis, a novel 64-bit reconfigurable adder is proposed and implemented to reduce the area and power consumption. This adder can be run-time reconfigured to different reconfigurable word lengths, i.e., one 64- bit, two 32-bits, four 16-bits or …
10-Bit C2c Dac Design In 65nm Cmos Technology, Jeevani Kommareddy
10-Bit C2c Dac Design In 65nm Cmos Technology, Jeevani Kommareddy
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Many wired and wireless communication systems require high-speed and high-performance data converters. These data converters act as bridge between digital signal processing blocks and power amplifiers. However, these data converters have been the bottleneck in the communication systems. This thesis presents the design of a 10-bit C2C digital to analog converter (DAC) for high resolution, wide bandwidth and low power consumption applications. The DAC is implemented in CMOS 65nm technology. The SFDR of this C2C DAC is 71.95dB at 500MHz input frequency and consumes 88.14µW of power with ENOB as 11.65 with 1.0GHz sample frequency with 0.31LSB of INL and …
Two Player Zero Sum Multi-Stage Game Analysis Using Coevolutionary Algorithm, Sumedh Sopan Nagrale
Two Player Zero Sum Multi-Stage Game Analysis Using Coevolutionary Algorithm, Sumedh Sopan Nagrale
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A New Two player zero sum multistage simultaneous Game has been developed from a real-life situation of dispute between two individual. Research identifies a multistage game as a multi-objective optimization problem and solves it using Coevolutionary algorithm which converges to a solution from pareto optimal solution. A comparison is done between individual stage behaviour and multistage behaviour. Further, simulations over a range for Crossover rate, Mutation rate and Number of interaction is done to narrow down the range for a range with optimal computation speed. A relationship has been observed which identifies a relationship between population size, number of interactions, …
System Identification And Model-Based Control Of Quadcopter Uavs, Andrew P. Szabo
System Identification And Model-Based Control Of Quadcopter Uavs, Andrew P. Szabo
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As control systems become more sophisticated, more accurate system models are needed for control law design and simulation. In this research, a nonlinear dynamic model of a quadcopter UAV is presented and model parameters are estimated off-line using in-flight experimental data. In addition, a model-based classical control law for the quadcopter UAV is designed, simulated, and then deployed in UAV flight tests. The intent of this research is to identify a model which may be simple enough to easily use for control law design, and accurate enough for simulation. In addition, a model-based classical control law is designed to for …
Display And Analysis Of Tomographic Reconstructions Of Multiple Synthetic Aperture Ladar (Sal) Images, Bassirou Seck
Display And Analysis Of Tomographic Reconstructions Of Multiple Synthetic Aperture Ladar (Sal) Images, Bassirou Seck
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Synthetic aperture ladar (SAL) is similar to synthetic aperture radar (SAR) in that it can create range/cross-range slant plane images of the illuminated scatters; however, SAL has wavelengths 10,000x smaller than SAR enabling a relatively narrow real aperture, diffraction limited beam widths. The relatively narrow real aperture resolutions allow for multiple slant planes to be created for a single target with reasonable range/aperture combinations. These multiple slant planes can be projected into a single slant plane projections (as in SAR). It can also be displayed as a 3-D image with asymmetric resolutions, diffraction limited in the dimension orthogonal to the …
Examination Of Gain Scheduling And Fuzzy Controllers With Hybrid Reachability, Aaron W. Fifarek
Examination Of Gain Scheduling And Fuzzy Controllers With Hybrid Reachability, Aaron W. Fifarek
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Modern aircraft with nonlinear flight envelopes predominately utilize gain scheduled controllers to provide stability of flight. Using gain scheduled control techniques, nonlinear envelopes can be linearized into collections of linear systems that operate under various system dynamics. Linear controllers approximate the nonlinear response over setpoints of operating conditions which allow traditional linear theory to be applied to maintain stability. Techniques to prove linear stability are well understood and realized in control systems, but when controllers are switched, interpolation methods must be used. Interpolation is necessary as gain scheduled systems do not have foundational switching paradigms as part of their realization …
Feed-Forward Compensation Of Non-Minimum Phase Systems, Venkatesh Dudiki
Feed-Forward Compensation Of Non-Minimum Phase Systems, Venkatesh Dudiki
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Due to inherent limitations posed by existence of zeros of a transfer function in the righthalfof the complex plane, known as non-minimum phase zeros, the issue of dealing withsuch zeros is extremely important in control of linear systems. Considerable literatureexists in control theory to try and minimize or eliminate the effect of non-minimum phasezeros. These include pole-zero cancellation, feedforward compensation, among others.These methods are only limited only to stable systems (systems with poles in the left halfof the complex plane); and will fail for systems that are unstable as well as non-minimumphase.This research focuses in designing feedforward compensators for unstable …
Switching Neural Network Systems For Nonlinear Tracking, Manoj Ghimire
Switching Neural Network Systems For Nonlinear Tracking, Manoj Ghimire
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In this thesis, we consider the problem of tracking in complex nonlinear dynamical systems. While the Kalman filter is known to be the mean-squared error optimal tracker under linear dynamics and linear measurements, more sophisticated models and algorithms are required for complex dynamics. Here, we consider switching systems where the dynamical properties vary (''switch modes") over time. For example, the dynamics of a vehicle may switch as it transitions from interstate to urban conditions, human speech dynamics switch as speakers change, and stock market dynamics switch with discrete news events. In this work, we use mode-dependent neural networks to capture …
Chaotic Based Self-Synchronization For Rf Steganography Radar/Communication Waveform, Michael A. Gonnella
Chaotic Based Self-Synchronization For Rf Steganography Radar/Communication Waveform, Michael A. Gonnella
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In this project, we continue previous CSR project entitled RF Steganography based Joint Radar/Communication Waveform Design to develop a bio-inspired secure low probability detection (LPD) radio frequency (RF) waveform that can serve multiple purposes simultaneously. Previously, we have developed an RF steganography based RF waveform to conceal a secure digital communication within a linear frequency modulated (LFM) chirp radar signal. By exploiting novel reduced phase shift keying modulation and variable symbol duration, the new waveform is resistant to time domain analysis, frequency domain analysis and cyclostationary analysis. However, to demodulate the hidden communication message, the intended receiver has to know …