Cable Noise in Impedance Measurements

cable noise;impedance measurements;twisted pair;twisted-pair period

Denenberg, Scott A. ; Cangellaris ; Andreas C.

关键词: cable noise;    impedance measurements;    twisted pair;    twisted-pair period;   

Others  :  https://www.ideals.illinois.edu/bitstream/handle/2142/18312/Denenberg_Scott.pdf?sequence=1&isAllowed=y

美国|英语

来源: The Illinois Digital Environment for Access to Learning and Scholarship

【 摘 要 】

This thesis focuses on the analysis of cable noise in impedance measurements.Specifically, the focus is on cables being developed for embedded sensing applications.In many applications, such as torque sensing and embedded fatigue and corrosion sensing, it is not feasible to have the probe electronics unit in close proximity to the material under test (MUT).Therefore, a cabling system is necessary to connect the sensors located on the MUT to the probe electronics.In many of these applications, especially those which require a higher frequency range into the MHz, the cable system is a significant source of noise. Noise contributed by this section of the cabling system is especially detrimental because it is added prior to the probe electronics signal amplification and conditioning.This thesis describes a study of the electromagnetic attributes of the current prototype cabling design with particular emphasis on the quantitative investigation of its sources of noise. A method for quantifying measurement noise due to the presence of external electromagnetic radiation is presented, and it is shown that, in general, the prototype cabling has sufficient shielding.Furthermore, a model is presented that explains measurement variation due to cable shape changes, especially cable twisting.