Print ISSN: 1811-9212

Online ISSN: 2617-3352

Keywords : Multi


Optimal Multi-objective Robust Controller Design for Magnetic Levitation System

Assist. Prof. Dr. Hazem I. Ali; Mr. Mustafa I. Abd

IRAQI JOURNAL OF COMPUTERS, COMMUNICATIONS, CONTROL AND SYSTEMS ENGINEERING, 2015, Volume 15, Issue 1, Pages 18-34

Abstract- In this work, the design of three types of robust controllers is presented to control the magnetic levitation system. These controllers are: basic H∞ controller, robust Genetic Algorithm (GA) based PID (GAPID) controller and robust Particle Swarm Optimization (PSO) based PID (PSOPID) controller. In the second and third controllers, the GA and PSO methods are used to tune the parameters of PID controller subject to multi-objective cost function (H∞ constraints and time domain specifications). The use of GA and PSO methods is used to simplify the design procedure and to overcome the difficulty of the resulting high order controller of the basic H∞ controller. The ability of the proposed controllers in compensating the system with a wide range of system parameters change is demonstrated by simulation using MATLAB 7.14.

Compact Size Design with low side lobes of Fractal Linear Array Antenna

Fawwaz Jinan Jibrael; at Talib Hussein; Dr. Refa

IRAQI JOURNAL OF COMPUTERS, COMMUNICATIONS, CONTROL AND SYSTEMS ENGINEERING, 2009, Volume 9, Issue 1, Pages 1-12

Abstract:
In this paper, the fractal concept is used in the linear array antenna design to obtain multiband operation and reduced size. MATLAB programming language version 7.2 (R2006a) is used to simulate the fractal linear array antenna and their radiation pattern. Fractal Cantor linear array antenna of array pattern of 101 has been designed at a frequency of 2700 MHz with uniform and non uniform amplitude distribution. The performance of this array has been simulated. It is found that it operates at frequencies 2700 MHz, 900 MHz, 300 MHz, and 100 MHz. Two proposed models of Cantor linear array antenna having array patterns of 11011 and 1010101 are presented with uniform and non uniform amplitude distribution. The performance of these arrays has been simulated. The resulting frequency behavior is found that it operates at frequencies 2700 MHz and 540 MHz for the first model (11011) and 2700 MHz and 386 MHz for the second model (1010101). The frequencies have been selected in the VHF and UHF bands have been used in many applications in communication systems such as global system mobile (GSM), wireless local area network (WLAN), worldwide interoperability for microwave access (WIMAX) …. etc.

3D COMBINED FRACTAL DIPOLE WIRE ANTENNA

at Talib Hussein; Refa

IRAQI JOURNAL OF COMPUTERS, COMMUNICATIONS, CONTROL AND SYSTEMS ENGINEERING, 2007, Volume 7, Issue 2, Pages 35-42

Abstract:

This work presents a numerical study for a new design of small size and multi-band fractal dipole antennas which is constructed by combining two fractal geometries to get the main antenna body. In this work a 3D combined fractal dipole antenna will be designed based on Hilbert and Koch curves to form the antenna geometry by using method of moment technique. Numerical simulations presented here also indicate that antenna size can be further reduced by 3D combined.