Worst case signal integrity analysis for in-vehicle data transmission via UTP cables

Future luxury car applications require reliable data transmission at higher data rates over copper cables. The unshielded twisted pair (UTP) cable is well proven for low data rates and is considered as a cost effective candidate for high speed data transmission. In this paper, the impedance of a UTP cable as a function of the distance to the car body is analyzed and a worst case impedance profile is identified. Resonances in frequency domain were measured and simulated, and their effect on time domain signals was analyzed for different bit patterns at various data rates.