11 research outputs found
Time delay and power control in spread spectrum wireless networks
Delay in the computation of the signal-to-interference ratio in communication systems is unavoidable. In the case of mobile communication, delay is a very critical problem due the fast variation of the communication channel and the need for effective, fast and accurate power control. In this paper we present our approach to dealing with the delay in mobile communication systems as well as our controller to achieve and maintain the desired signal quality. We will concentrate on the code division multiple access (CDMA) systems
Control and systems engineering: a report on four decades of contributions
This book is a tribute to 40 years of contributions by Professor Mo Jamshidi who is a well known and respected scholar, researcher, and educator. Mo Jamshidi has spent his professional career formalizing and extending the field of large-scale complex systems (LSS) engineering resulting in educating numerous graduates specifically, ethnic minorities. He has made significant contributions in modeling, optimization, CAD, control and applications of large-scale systems leading to his current global role in formalizing system of systems engineering (SoSE), as a new field. His books on complex LSS and SoSE have filled a vacuum in cyber-physical systems literature for the 21st Century. His contributions to ethnic minority engineering education commenced with his work at the University of New Mexico (UNM, Tier-I Hispanic Serving Institution) in 1980 through a NASA JPL grant. Followed by several more major federal grants, he formalized a model for educating minorities, called VI-P Pyramid where K-12 students(bottom of pyramid) to doctoral (top of pyramid) students form a seamless group working on one project. Upper level students mentor lower ones on a sequential basis. Since 1980, he has graduated over 114 minority students consisting of 62 Hispanics, 34 African Americans., 15 Native Americans, and 3 Pacific Islanders. This book contains contributed chapters from colleagues, and former and current students of Professor Jamshidi. Areas of focus are: control systems, energy and system of systems, robotics and soft computing
Time delay and power control in spread spectrum wireless networks
Delay in the computation of the signal-to-interference ratio in communication systems is unavoidable.
In the case of mobile communication, delay is a very critical problem due the fast variation of the communication channel and the need for effective, fast and accurate power control. In this paper we present our approach to dealing with the delay in mobile communication systems as well as our controller to achieve and maintain the desired signal quality. We will concentrate on the code division multiple access (CDMA) systems.International Federation of Automatic Control (IFAC
Application of Radio Control Cars as Intelligent Unmanned Ground Vehicles with Collaborative and
Simple radio control cars commonly sold as toys can provide a viable starting platform for the development of low-cost intelligent Unmanned Ground Vehicles (UGVs) for the study of robot collectives. In a collaborative effort, Sandia National Labs and New Mexico Tech have successfully demonstrated proof-of-concept by utilizing low-cost radio control cars manufactured by Nikko. Initial tests have involved using a small number (two to ten) of these UGVs to successfully demonstrate both collaborative and independent behavior simultaneously. In the tests individuals share their locations with the collective to cover an area, thus demonstrating collaborative behavior. Independent behavior is demonstrated as each member of the collective maintains a desired compass heading while simultaneously avoiding obstacles in its path. These UGVs are powered by high-capacity rechargeable batteries and equipped with a custom-designed microcontroller board with a stackable modular interface and wireless communication. The initial modular sensor configuration includes a digital compass and GPS unit for navigation as well as ultrasonic sensors for obstacle avoidance. This paper describes the design and operations of these UGVs, their possible uses, and the advantages of using a radio control car platform as a low-cost starting point for the development of intelligent UGV collectives