Analyzing and Mitigating the Near-field Radiations from PCB of GPS-based Vehicle Tracking System

Abstract

The EMI/electromagnetic compatibility (EMC) analysis is becoming very important in today’s world of dense EMI environment. As we go toward accuracy and stability of any electronic product in dense EMI field, it is necessary to test it at printed circuit board (PCB) level. This paper describes the measurement technique of scanning of PCB using EMC Precision Scan Tool. The result of near-field measurement indicates the intensity of radiation of each component on PCB. This study is proposed to estimate the radiation field at component level. The near-field based techniques have been widely used in EMC studies because of the high accuracy and reliability. With appropriate model extraction and simulation tools, near-field scanning can be used to predict electromagnetic emissions. With proper shielding, the near-field radiations can be reduced. The near-field radiations can be used to predict far-field radiations from the system, before practically testing in EMI/EMC Laboratory or getting installed at end-user applications. Two models for global positioning system (GPS)-based vehicle tracking system used in research work have been proposed in this article. One is GPRS based and the other is SMS based, intended to be used in stringent environment and ground-based army vehicle. The near-field radiations have been taken at PCB level in dB ¼V for a range of 100 kHz-2.5 GHz frequency band. Maximum radiations of around 90–130 dB ¼V were found. The paper proposes Mu-metal and HE-30 shielding materials for mitigating low- and high-frequency radiations. The GPS VTS GPRS based board and GPS VTS SMS Tx board with HE-30 enclosures had been tested in national EMI Test Laboratory, Automotive Research Association of India (ARAI), for the frequency bands 100 KHz-2.5 GHz. The results had been compared with MIL-461E EMI/EMC standard, and had been found to be satisfactory. The low-frequency radiation level was found to be just within the acceptable limits as per the standard.

Keywords:

• Electromagnetic compatibility
• Electromagnetic interference
• Mu-metal
• Near field
• Printed circuit board
• Radiation

Additional information

Notes on contributors

Shreenivas R. Jog

Shreenivas R. Jog has submitted Ph.D. in E and TC at the College of Engineering Pune, affiliated to University of Pune, India. He has completed B.E. and M.E. (E and TC) from the College of Engineering, Pune. He has 23 years of experience in academics/R and D. His areas of interest include GPS, Mobile and Wireless Communication, EMI/EMC, Ruggedized and Defense Communications Systems. He has published 46 papers in national and international conferences/journals. He is presently working as the Professor and HOD (E and TC) in Pd. Dr. D. Y. Patil Institute of Engineering and Technology, Pimpri, Pune. He is a fellow of IETE and also a member of IEEE, IEEE Communication Society, IEEE EMC Society, I E (I), and ISTE. He is presently working as the Chairman, IETE Pune Center. He is also an ex-officio member of the governing council of IETE. He is a member of Publication and Technical Programme Committee of IETE at the national level. E-mail: [email protected]

Isha Deshpande

Isha Deshpande has submitted M.E. in E and TC at Dr. D. Y. Patil institute of Engineering and Technology, Pimpri, affiliated to University of Pune, India. She has completed B.E. in E and TC at Padmabhushan Vasantdada Patil Institute of Technology, Budhgaon, affiliated to Shivaji University. She has 3 years of experience in academics. She has published two papers in national/international conferences/journals. E-mail: [email protected]

M. S. Sutaone

M. S. Sutaone is working as the Head of E and TC Department, College of Engineering, Pune, and he has 25 years of experience in academics. He has published more than 40 papers in national/international conferences/journals. His areas of interest include DSP, Image Processing, Mobile, VLSI, and Wireless Communications systems. E-mail: [email protected]

V. V. Badawe

V. V. Badawe is the Director, BEPL, Pune, India. He has more than 40 years of experience in R and D. His areas of interest include Microwaves, Antennas, Radar, and Defense Wireless Communications systems, Ruggedization of systems, and EMI/EMC. E-mail: [email protected]