Analog Communication Systems Research Articles

Quantum Multipartite correlation in Optical channel

The communication in the quantum networks is based on optical channels to take the advantage of analog, optical and digital communication system. Single data which carries information over the channel can be termed as solid state atoms or photons. The reliable channel is the one which carries the same state from the sending node to destination there can be superposition of states. practically ideal channel does not exist, the optical Gaussian channel which is considered as a degradable quantum channel. The optical interfaces and standard signal format would allow interconnecting fiber optic transmission equipment through multiple networks which carries information generated by multiple users of the network. Taking the infrastructure of existing telecommunication use the quantum information so that it is secure by its nature.

A new 4-D hyperchaotic hidden attractor system: Its dynamics, coexisting attractors, synchronization and microcontroller implementation

In this paper, a simple 4-dimensional hyperchaotic system is introduced. The proposed system has no equilibria points, so it admits hidden attractor which is an interesting feature of chaotic systems. Another interesting feature of the proposed system is the coexisting of attractors where it shows periodic and chaotic coexisting attractors. After introducing the system, the system is analyzed dynamically using numerical and theoretical techniques. In this analysis, Lyapunov exponents and bifurcation diagrams have been used to investigate chaotic and hyperchaotic nature, the ranges of system parameters for different behaviors and the route for chaos and coexisting attractors regions. In the next part of our work, a synchronization control system for two identical systems is designed. The design procedure uses a combination of simple synergetic control with adaptive updating laws to identify the unknown parameters derived basing on Lyapunov theorem. Microcontroller (MCU) based hardware implementation system is proposed and tested by using MATLAB as a display side. As an application, the designed synchronization system is used as a secure analog communication system. The designed MCU system with MATLAB Simulation is used to validate the designed synchronization and secure communication systems and excellent results have been obtained.

Photonic Armstrong method enabled by direct detection for wideband electrical PM generation.

Wideband signal generation using frequency/phase modulation (FM/PM) is the key fundamental function for various applications such as radar and analog communication systems. It is well known that analog FM/PM communication systems can dramatically improve signal quality by spectral expansion. In classical communication theories, the Armstrong indirect method is one of the most popular methods for bandwidth expansion of FM signals. In the Armstrong method, a narrowband signal is converted to a broadband signal with the help of a nonlinear frequency multiplier. In this paper, we propose a photonic Armstrong method enabled by direct detection. By utilizing the nonlinearity caused by direct detection, we can increase bandwidth so that it is double that of the original signal in the photonic Armstrong method. Also, it completely eliminates signal-to-signal beat interference (SSBI) at the same time. We conducted an experiment to verify the concept and confirmed these advantages experimentally.

Schmitt Trigger Circuits using Various Active Devices

A vast number of diverse analog circuit blocks have been arosed in the past few decades. A various active devices are Operational Amplifier (Op-Amp), Current Conveyor (CC), Operational Transconductance Amplifier (OTA), Differential Difference Current Conveyor (DDCC), Differential Difference Current Conveyor Transconductnace Amplifier (DDCCTA), Z-Copy Current Differencing Transconductance Amplifier (ZC-CDTA), Voltage Difference Transconductance Amplifier (VDTA) and so on. A review on Schmitt trigger circuits by using different active devices are presented in this paper since Schmitt trigger circuits are widely used in numerous applications such as in waveform generators, wave-shaping circuits, comparators, Bio-medical applications, analog processing systems, communication and instrumentation systems.

Schmitt Trigger Circuits using Various Active Devices

A vast number of diverse analog circuit blocks have been arosed in the past few decades. A various active devices are Operational Amplifier (Op-Amp), Current Conveyor (CC), Operational Transconductance Amplifier (OTA), Differential Difference Current Conveyor (DDCC), Differential Difference Current Conveyor Transconductnace Amplifier (DDCCTA), Z-Copy Current Differencing Transconductance Amplifier (ZC-CDTA), Voltage Difference Transconductance Amplifier (VDTA) and so on. A review on Schmitt trigger circuits by using different active devices are presented in this paper since Schmitt trigger circuits are widely used in numerous applications such as in waveform generators, wave-shaping circuits, comparators, Bio-medical applications, analog processing systems, communication and instrumentation systems.

Quality Verification of Audio and Image Modulation by the Simulation of PCM, DM and DPCM Systems

Modulation is a process through which a message has to pass in order to be effectively transmitted. However, there are some limitations to Pulse Code Modulation and Delta Modulation that can cause data redundancy, quantization error, slope overload distortion and granular noise which result in a bad communication process. Throughout the past few years, Pulse Code Modulation (PCM), Delta Modulation (DM) and Differential Pulse Code Modulation (DPCM), in digital communication systems, have proven to have unparalleled advantages over analog communication systems; this is in terms of error minimization and distances of transmission enhancements. Delta Modulation, a simplified version of Pulse Coded Modulation also pauses major problems in noise and quantization error. Consequently, and to combat the arising problems, communication engineers have developed newly adaptive compression and modulations techniques for better digital transmission. One of these innovative systems is the Differential Pulse Coded Modulation (DPCM) that can solve the aforementioned problems. Thus the focal point of this article is to explore the simulation of these systems using Simulink (The Math Works, Inc., USA). Eventually, the systems are tested on both image and audio inputs to prove the superiority of DPCM over DM and PCM systems in reducing noise and increasing the signal to quantization noise ratio, thus insuring a smooth and successful transfer of data.

Development of Analog and Digital Communication Systems Experimental Set for Time Division Multiplex Topic

Development of Analog and Digital Communication Systems Experimental Set for Time Division Multiplex Topic

Real-Time Estimation of Battery State of Charge With Metabolic Grey Model and LabVIEW Platform

Accurate state-of-charge (SoC) estimation is crucial to guarantee the safety and reliability of lithium-ion batteries. This paper aimed to develop an advanced battery estimation method for electric vehicles based on the grey model without the need of a high-fidelity battery model demanding high computation power. The metabolic grey model (MGM) introduced metabolism mechanism to adjust the model parameters according to the evolving operating status and conditions and estimate the state of charge. To further validate the feasibility of the proposed method, the analog acquisition, communication system, and SoC estimation algorithms were programmed to embed within a LabVIEW platform. The performance of the proposed SoC estimation with MGM algorithm was finally investigated with a battery-in-loop platform under different dynamic loading profiles. The experimental results indicated that the MGM can estimate SoC that involved small samples and poor information in real time, with the maximum errors of no over 4% under various loading conditions.

Designing MATLAB GUI for various Analog and Digital Communication Systems

Designing MATLAB GUI for various Analog and Digital Communication Systems

ANALYSIS AND SIMULATION OF RAYLEIGH FADING CHANNEL IN DIGITAL COMMUNICATION

The objective of this paper is to analyze slow, flat, Rayleigh fading channels in modern digital communication systems having different coherent modulation techniques. Most of the packages can only be used to analyze analog communication systems, but modern systems are, increasingly, digital. Improved many-on-many (IMOM) is a two-dimensional, graphical-oriented, radio frequency modeling tool is used to determine probability of channel bit error rather than information bit error, which allows generic solutions independent of the specifics of the system under investigation as long as the particular modulation type is known. Constellation diagram of various modulation techniques, power of faded signal and signal at receiver are plotted in MATLAB environment. The Joint Tactical Information Distribution System (JTIDS) is suitable example of this analysis.

Real-time estimation of battery state-of-charge with unscented Kalman filter and RTOS μCOS-II platform

To develop an advanced battery estimation unit for electric vehicles application, the state-of-charge (SoC) estimation is proposed with an unscented Kalman filter (UKF) and realized with the RTOS μCOS-II platform. Kalman filters are broadly used to deploy various battery SoC estimators recently. Herein, an UKF algorithm has been employed to develop a systematic adaptive SoC estimation framework. Compared with traditional used extended Kalman filter, it uses an unscented transform to deal with the state estimation problem, thus it has the potential to achieve third order accuracy of the Taylor expansion for tracking posterior estimate of the inner inhabited state. Beneficial from it, the SoC estimation accuracy has been improved with higher tracking accuracy and faster convergence ability. To further evaluate and verify the performance of the proposed online SoC estimation approach, a battery-in-loop platform is built and the SoC estimation is calculated with a RTOS μCOS-II platform. The analog acquisition, communication system and SoC estimation algorithms were programmed, the performance of the proposed SoC estimation with UKF algorithm was finally investigated. The battery management system with UKF algorithm and RTOS μCOS-II platform has good performance and it can apply for electric vehicles.

Adaptive Control for Laser Transmitter Feedforward Linearization System

In this paper, an adaptive control system is employed in a novel implementation technique of the feed forward linearization system for optical analog communication systems' laser transmitter. The adaptive control system applies the Newton trust-region dogleg algorithm, which is a numerical optimization algorithm, to automatically tune the adjustment parameters in the feed forward loops to optimize the feed forward system performance and adapt to process variations. At the end of this paper, significant reductions of over 20 dBm in the third-order inter modulation distortion products have been achieved for operating frequencies from 5.0 to 5.8 GHz.

Lithium-ion Battery SoC Estimation with UKF and RTOS μCOS-II Platform

To develop a battery management system for lithium-Ion batteries used in electric vehicles, the state of charge (SoC) estimation is improved with an unscented Kalman filter (UKF) and realized with the RTOS μCOS-II platform. The Kalman filters approach is broadly used for the battery SOC estimation recently. Here, we select the UKF algorithm, for which utilizes the unsented transform to solve filtering problems and is able to accurately capture the posterior mean and covariance to 3rd order of Taylor series expansion, as a result, the SoC estimation accuracy is improved with a faster convergence ability. To further evaluate the real-time performance of the SoC estimation, a battery-in-loop platform is built and the SoC estimation is calculated with a RTOS μCOS-II platform. The analog acquisition, communication system and SoC estimation algorithms were programmed, the performance of the proposed SoC estimation with UKF algorithm was finally investigated. The battery management system with UKF algorithm and RTOS μCOS-II platform has good performance and can apply for electric vehicles.

SAKA: a secure authentication and key agreement protocol for GSM networks

Although nowadays we are running in the 3rd generation of cellular networks but most of the service providers are also providing the services of 2nd generation cellular networks. The Global System for Mobile Com- munication (GSM) protocol is proposed to solve the security issues and vulnerabilities found in first generation of cellular communication which was based on analog communication system. GSM system is still vulnerable to redirection attack, man-in-the-middle attack and imper- sonation attack. An intruder can apply these attacks to impersonate the network or bill mischarge the users. In this paper, we propose a new secure GSM protocol called ''SAKA'' to prevent GSM networks from various security issues and attacks. This proposed protocol improves the drawbacks of the original GSM authentication protocol including: not supporting mutual authentication; large bandwidth consumption between VLR and HLR; storage space overhead in VLR; and overloaded HLR with authentication of mobile stations. This protocol also elim- inates the need of synchronization between a mobile station MS and its home network HLR. The SAKA protocol generates minimum communication overhead as compare to all other existing and proposed GSM protocols. Authors claim that on an average the SAKA protocol has reduced 56 % of the bandwidth consumption during the authenti- cation process which is the maximum reduction of band- width by any GSM protocol.

Modern analog and digital communication systems development using GNU Radio with USRP

In this modern world many communication devices are highly intelligent and interconnected between each other. Any up-gradation of the hardware in the existing communication devices is not easier one. Compatibility of the new hardware with existing hardware is highly essential. But the new protocols may or may not support the older one. The solution for these problems can be provided by using the reconfigurable hardware design. The hardware can be reprogrammed according to the new change in technology up-gradation. The cost of commercially available hardware and software requirements for setting up such a module is very high. This can be solved by using Open source hardware and software such as Universal Software Radio Peripheral (USRP) and GNU Radio. This work demonstrates how the modern analog communication system like Community Radio Schemes and Radio Data System (RDS) and digital communication systems such as Simple Digital Video Broadcasting (DVB) and OFDM based data communication can be developed using the Open source hardware USRP1. This work will be helpful even for first year level of engineering students to easily implement any communication and control applications with cheaper cost.

H∞ SYNCHRONIZATION OF SWITCHED CHAOTIC SYSTEMS AND ITS APPLICATION TO SECURE COMMUNICATIONS

This paper deals with the H∞ synchronization problem of switched chaotic systems accompanied by a time-driven switching law and its application to secure communications. Based on the Lyapunov stability theory and linear matrix inequality (LMI) and linear matrix equality (LME) optimization techniques, an output feedback controller that guarantees the synchronization of switched master-slave chaotic systems is designed. A chaotic encryption technique that uses synchronization is proposed for securely transmitting a message over public channels. Numerical simulations of both analog and digital security communication systems are conducted to demonstrate the effectiveness of the proposed methods.

Analysis of a Deconvolution Algorithm for quantized-input linear systems through Iterated Random Functions

AbstractDeconvolution consists in recovering the unknown input of a system given noisy measurements of the output. If the input is quantized, the problem can be faced via Information and Decoding techniques, which provide the suitable tools to work in hybrid contexts, namely when discrete signals are transmitted through analog communication systems. Derived from BCJR, a low-complexity, recursive decoding algorithm has been developed by Fagnani and Fosson (2009) and is here applied to tackle deconvolution of one-dimensional linear systems with binary input. The aim of the paper is to provide a rigorous mathematical analysis of the performance of such algorithm, in terms of a mean square error and for long time transmissions. This task is accomplished by means of Iterated Random Functions.

Analog and digital signals and systems

This book presents a systematic, comprehensive treatment of analog, discrete signal analysis and synthesis and an introduction to analog communication theory. The material is divided into five parts. The first part (Chapters 1-3) is mathematically oriented and deals with continuous-time (analog) signals. The second part (Chapters 4-5) is again mathematically based and deals with Fourier transforms, Hartley transforms, Laplace and Hilbert transforms. The third part (Chapters 6-7) presents basic system analysis, approximations, and analog filter circuits using op-amps. The fourth part (Chapters 8-9) deals with discrete signals, fast algorithms and digital filters. The fifth part deals with an introduction to analog communication systems.

A new look at the classical key exchange system based on amplified Johnson noise

A classical key exchange system based on the amplified Johnson noise has been proposed and demonstrated recently. In this Letter, a modified system is presented. By using circulator and feedback, the new system can be compatible with traditional analog and digital communications systems using carrier waves. Results of circuit simulations, however, indicate that the signal transit time poses a serious risk. Because of delay and multiple reflections, there is always a difference between two parties communicating. The eavesdropper can exploit this difference. By choosing impedance and delay time, the difference can be reduced. Nevertheless, the system is far from being secure except when two parties are collocated.

Design and Assessment of a High Gamma-Dose Tolerant VCSEL Driver With Discrete SiGe HBTs

A digital VCSEL driver has been designed, simulated and assessed under radiation, using discrete SiGe HBT's. The circuit tolerates high levels of gamma radiation, up to 12 MGy, features less than 2% drift in the forward current of the VCSEL and operates well above 10 MHz. The output duty cycle shows no notable degradation at 200 kHz, enabling the design of robust analog and digital communication systems using pulse-width-modulation (PWM) schemes.