Analysis of Radio Disturbance Measurement Techniques for Automotive Application

This paper gives an overview of the main issues about radio disturbances measurements. To predict the noise level at the car radio antenna input, tests on isolated devices are performed on bench. The CISPR-25 standard contains the limits and procedures for radio disturbances measurements. Although on-bench results comply with the standard, they do not guaranty final validation on vehicle: development time may be lengthened. For a better understanding of the validation tests, a first study, which deals with the identification of the influent measurement factors, has begun. We performed comparison between tests on bench and their transposition on vehicle or in a half size canonical car model. The first results show dispersion on the obtained measurements that goes up to 10 dB. We will proceed with a design of experiment method [6] whose key points are its efficiency and the handling of interaction between factors. We are also going to proceed with a hybridization of tests and numerical simulation. This technique will allow us to predict the emission level required on bench to assure the final validation on vehicle. For the future work prospects, we are going to try a partial transposition on bench, of the vehicle measurement configuration.