Achieving optimal design of phase-locked loop (PLL) is a major challenge in WiMax technology in order to improve system behavior against noise and to enhance Quality of Service (QOS). A new loop filter design method for phase locked loop (PLLs) is introduced taking into consideration various design objectives: small settling time, small overshoot and meeting Mobile WiMax requirements. Optimizing conflicting objectives is accomplished via linear programming and semidefinite programming (especially Linear Matrix Inequality (LMI)) in conjunction with appropriate adjustment of certain design parameters. Digital filters, Infinite Impulse Response (IIR) and Finite Impulse Response (FIR) are designed using linear programming and convex programming.Simulations show that IIR digital lowpass filter with narrow transition band could not work properly with mobile WiMax system. Simulations show that FIR digital lowpass filter utilizing linear programming managed to improve the transient behavior. The FIR digital lowpass filter utilizing semidefinite programming (LMI) will much improve the transient behavior; therefore it is recommended for mobile WiMax systems.
Achieving an optimal design of phase-locked loop (PLL) is a major challenge in WiMAX technology in order to improve system behavior against noise and to enhance Quality of Service (QoS). A new loop filter design method for PLL is introduced taking into consideration various design objectives such as small settling time, small overshoot and meeting Fixed WiMAX requirements. Optimizing conflicting objectives is accomplished using semi-Definite programming (especially Linear Matrix Inequality (LMI)) in conjunction with appropriate adjustment of certain design parameters. Infinite Impulse Response (IIR) and Finite Impulse Response (FIR), Digital filters are designed by Semi-Definite Programming (SDP) using SeDuMi (self-dual minimization) toolbox software. Design efficiency and performance of the proposed method are illustrated by simulations and comparisons to other design methods. Simulations showed that the IIR which was designed by SDP is better than the IIR which designed by Linear Programming (LP).Also, the FIR which was designed by SDP using SeDuMi software is better than the FIR which was designed in by SDP using CVX (convex optimization tool) software.
A phase locked loop (PLL) plays significant role in analog and digital systems. It is a control system that generates an output signal in-phase of the input reference signal. This report has presented a low-power PLL implemented in 130nm CMOS technology for communication systems. The improved power efficient design of PLL consists of a phase detector; a charge pump, low pass filter, and bulk driven three stage ring VCO. The VCO is the main part PLL design. The proposed three, five and seven stages ring VCOs are presented in this report. The proposed three stage ring VCO shows better performance in terms of tuning range (917.43 MHz-4189.53 MHz) and power consumption (14.67µW). The output frequency of VCO shows almost linear relationship with the control voltage. The key design objectives of PLL are size, power consumption, lock range and frequency range of the VCO. The proposed low power, small area PLL has great potential in implantable bio-medical and wireless systems.
This book presents an innovative approach to detect computational fault using design for testability (DFT) of CP-PLL (charge pump phase locked loop) to allow simple digital testing. The proposed structure is useful in mixed signal IC (incorporating both analog and digital block on the same chip) testing. With increasing complexity of mixed signal IC the demand of preparing the low cost testing circuitry also gets increased. Here CP-PLL is taken as the mixed signal IC wherein the proposed method uses the charge pump as stimulus generator and the VCO (voltage controlled oscillator) as measuring device for testing the CP-PLL. It avoids the need of interfacing any foreign component and decreases the area overhead of whole IC. Moreover, testing circuitry is applied at the digital part of the CP-PLL i.e. PFD (phase frequency detector) and the analog part i.e. charge pump; loop filter and VCO are controlled by PFD only. Consequently the efficiency of the testing process avoiding the loading effect at analog node is increased. Fault simulation results indicate that the proposed structure posses high fault coverage of 98.2% and less area overhead of about 3.025%.
Telecommunication industries are highly concerned with the wireless transmission of data which can use various transmission modes, from point- to-multipoint links. It contains full mobile internet access. Various applications have already been applied so far using WiMAX, as alternative to 3G mobile systems in developing countries, Wireless Digital Subscriber Line, Wireless Local Loop . IEEE 802.16e-2005 has been developed for mobile wireless communication which is based on OFDM technology and this enables going towards the 4G mobile in the future. In this thesis work, we built a simulation model based on 802.16e OFDM-PHY baseband and demonstrated in different simulation scenarios with different modulation techniques such as BPSK, QPSK and QAM (Both 16 and 64) to find out the best performance of physical layer for WiMAX Mobile. All the necessary conditions were implemented in the simulation according to 802.16e OFDMA-PHY specification. The noise channel AWGN, Rayleigh fading, SUI, data randomization techniques, FFT and IFFT, and Adaptive modulation is used for the whole simulation procedure. Performance has been concluded based on BER, SNR and Pe output through MATLAB Simulation.
In this project, Verilog HDL is used for the implementation due to its compatibility with pure digital hardware like FPGA’s. The Digital PLL is simulated and verified on FPGA to experience its advantages. The circuit comprises of a phase detector, loop filter, Numerically Controlled Oscillator (NCO), and two clock dividers. The circuit was stabilized to produce the frequency in the audio frequency range of 9.7 KHz. This agreed with the classical phase-locked loop model for the system. The stable long-term frequency clock was verified on the FPGA to generate the required locking frequency. The DC logic synthesis and a new synopsis low power flow was experimented for back annotation and to obtain the maximum possible operating frequency and area, timing and power estimation.
Written and edited by experts who have developed WiMAX technology and standards WiMAX, the Worldwide Interoperability for Microwave Access, represents a paradigm shift in telecommunications technology. It offers the promise of cheaper, smaller, and simpler technology compared to existing broadband options such as DSL, cable, fiber, and 3G wireless. WiMAX Technology and Network Evolution is the first publication to present an accurate, complete, and objective description of mobile WiMAX technology. Each chapter was written and edited by experts, all of whom have been directly engaged in and lead the development of WiMAX either through the IEEE 802.16 Working Group or the WiMAX Forum. As a result, the book addresses not only key technical concepts and design principles, but also a wide range of practical issues concerning this new wireless technology, including: Detailed description of WiMAX technology features and capabilities from both radio and network perspectives WiMAX technology evolution in the near and long term Emerging broadband services enabled by the WiMAX networks Regulatory issues affecting WiMAX deployment and global adoption WiMAX accounting, roaming, and network management Each chapter ends with a summary and a list of references to facilitate further research. Wireless engineers, service designers, product managers, telecommunications professionals, network operators, and academics will all gain new insights into the key issues surrounding the development and implementation of mobile WiMAX. Moreover, the book will help them make informed management and business decisions in devising their own WiMAX strategies.
In modern control systems, physical plant, controller, sensors and actuators are difficult to be located at the same place, and hence these components need to be connected over network media. When feedback control system is closed via a communication channel, then the control system is classified as a Networked Control Systems (NCS). This book presents the design of dissipative control system for NCS. The dissipativity analysis with quadratic supply function is quite general which includes H? and passivity as special cases. The NCS is modelled as a time delay systems. Two network features are considered: signal transmission delay and data packet dropout. Our objective is focused on the design of state feedback controller which guarantee asymptotic stability of the closed-loop systems. The proposed methods are given in the terms of Linear Matrix Inequality (LMI). If this LMI conditions feasible, a desired controller can be readily constructed. Finally, we consider an unstable system for systems simulation. It is shown that the state feedback controller proposed here make the closed-loop system stable with or without input disturbance.
Modern cellular phones and base stations have to serve a multitude of wireless communication standards with each standard using different frequency bands. For such applications, a universal programmable hardware is desirable which is often referred to as software-defined radio (SDR). This book describes agile frequency synthesizers representing key building blocks for an SDR transceiver. In this work, an innovative frequency generation scheme is derived to provide a multi-octave tuning range with very low phase noise and low spurs. A PLL phase noise model including a nonlinear phase detector is thoroughly discussed. Design techniques for low phase noise VCOs with mixed analog/digital tuning are presented. Further, the book investigates both single-loop and dual-loop PLL architectures in fractional-N synthesizers. An unconventional two-transistor based charge pump in a dual-loop PLL improves phase detector linearity and reduces charge pump noise. This results in a low in-band phase noise similar to an integer-N synthesizer. Finally, the book presents the design of fully integrated integer-N and fractional-N frequency synthesizers with detailed measurement results.
With the development in internet applications and multimedia technology, users are accustomed to high-speed broadband at home and work and demand similar services even in nomadic or mobile environment. Mobile WiMAX provides broadband wireless access with mobility, large coverage and security. WiMAX physical layer is based on Orthogonal Frequency Division Multiplexing which mitigates multipath and eliminate intersymbol interference with the help of cyclic prefix. Scalable OFDMA on its physical layer allows data rate to scale with available channel bandwidth. WiMAX supports a number of modulation (BPSK, QPSK, 16-QAM & 64-QAM) and forward error correction coding scheme and can operate in both line of sight and non-line of sight environments. In this book, the performance of physical layer of mobile WiMAX is evaluated at different modulation schemes, coding rate, FEC coding schemes and noise levels with models of multipath fading channel based on the specification of IEEE Std. 802.16-2009. Scatter plots and SNR vs BER plot are obtained as performance analyzer. GUI tool is developed in MATLAB for simulation which can be useful for research scholar to simulate physical layer of WiMAX
I am proud to present my book which I believe will prove as a milestone in various engineering projects. My aim is to design and fabricate an industrial system communicating between two stations connected wirelessly via WiMAX. It covers all the technical details and focuses on its application in various industrial processes. WiMAX is an emerging technology which is gaining ground these days. The reason for publishing such a book is to cater for today’s growing needs of automation in industries. Monitoring instruments and sensors wirelessly is today’s demand. It decreases cabling costs and installation time and is ideal in electrically noisy or hostile environments. It can decrease human intervention by making the machinery automatic, save the operator from tedious job of continuous monitoring and avoid unauthorized usage hence increasing the accuracy and security of the system. It also covers the future applications of WiMAX e.g. Cellular networks, Broad-band access etc. I therefore conclude that this book is not specifically for industrial automation rather it can be considered as a powerful tool that formulates the basic building block of the wireless technology WiMAX.
This book contains a robust and efficient dynamic technique for load balancing in WiMAX. WiMAX is one of the most recent broadband wireless technology that based on IEEE 802.16 standard and its amendments. This technique makes sure of balancing among all base stations in the whole network. It also take into account the quality of service parameters for real-time applications such as voice over Internet Protocol and video conferencing.
In these days, WiMAX (Worldwide Interoperability for Microwave Access) is an eminent technology that provides broadband and IP connectivity on “last mile” scenario. It offers both line of sight and non line of sight wireless communication. OFDMA uses the concept of cyclic prefix that adds additional bits at transmitter end. The receiver removes these additional bits in order to minimize the inter symbol interference (ISI), to improve the bit error rate and to reduce the power spectrum. All of these technologies based on cellular networks are comprised of cells. Number of available channels in a cell is limited and due to this limitation if traffic in the cell is high users may face call terminations and may be blocked by the cell completely. Due to lack of high data rates GSM is not able to support wireless broadband users. WiMAX has support for wireless broadband users, both fixed and mobile. At present, WiMAX is emerging fast and operators are implementing for commercial use. An algorithm for analyzing different system parameters and traffic cases to ease the Mobile WiMAX planning problem is given and simulated.