EMI Suppression Techniques for Broadcast Reception in Electric Vehicles

Electric driven vehicles become more and more important in today\´s mobile world. In addition to all its benefits, this technology has some drawbacks. Due to the electrical drive system, we measure higher voltages and higher currents. This is the reason why we get more electromagnetic interference (EMI) in the electric vehicle (EV). The highest requirements regarding EMI result from broadcast reception systems. The conventional approach of noise suppression with passive, active or hybrid filter structures and shielding increases the costs and the weight of the vehicle. In this paper a concept is presented, where the expensive shielding is replaced or supported by digital signal processing in the tuner. The active noise suppression can be supported by additional field probes. Therefore, the tuner can receive more information about the interferers. This principle works like the well-known "Active Noise Cancelling" (ANC). The algorithms have to be developed individually for each broadcast standard and are derived in this presentation for FM, AM and DVB T. Simulation results of the new approach demonstrate dramatic performance improvement in an EMI burdened car environment.