Analysis of electromagnetic wave propagation by using Poynting vector in automobile

Abstract

Conventional methods used to clarify electromagnetic noise propagation in a vehicle have mainly concentrated on the measurement of electric and magnetic fields, but if we measure the way in which the electromagnetic energy is being transmitted from the source, this will make it possible to take more effective action against such electromagnetic noise. This paper describes a method using a tri-axial magnetic probe in the vehicle to detect the near magnetic field, whereupon the electric field is obtained by calculating it from the magnetic field and from this, the Poynting vector, which indicates energy flow, is calculated. Using this method, it is possible to visualize the energy flow of electromagnetic wave generated by antennas in the vicinity of the vehicle and electromagnetic noise generated from the vehicle.

Circular folded dipole antenna for RFID tag on metallic cylinder

“…The standard of the frequency range is from 916.7 MHz to 923.5 MHz in Japan [2]. The electromagnetic environments inside and outside a car have also been investigated [3,4]. The evaluation of the radio wave propagation in the engine room and outside a vehicle from the engine room achieved a shortrange wireless sensor network on the car engine room with narrow and complicate spaces [5].…”