Parameter measurement of UTPs and crosstalk analysis

Unshielded twisted pairs (UTPs) are widely used in CAN bust system to decrease interference. In order to predict the interference from external environment, the PUL parameters of UTPs must be gained. By measuring the input short- and open-circuit impedances, the transmission line parameters of unshielded twisted pairs are gained. The FDTD method is used to simulate the transient process of UTPs (crosstalk). The experimental test results are consistent with simulation results, it illustrates the method of parameters measure is validity. The test method can be used to measure the parameters which are not easy to gain by simulation or computation.