Microwave propagation characterization in automotive engine compartment for wireless harness communications

In this paper, the path loss in the automotive engine compartment is characterized in a frequency range from 2 GHz to 20 GHz for the development of a future wireless-harness communication enabling wireless interconnections between modules and sensors. As an important factor of the propagation, the path-loss exponent is extracted from measured frequency characteristics of the path loss. The key findings of this paper are as follows: 1) The attenuation factor for the propagation distance shows a low frequency dependency in the line-of-sight (LOS) case, while it increases from 1 to 4 as the frequency is higher in the non-line-of-sight (NLOS) case, and 2) the attenuation factor for the frequency is lower than 2 of the free-space propagation.