Capacitance Modelling of Conductive Cotton Knit Fabric for Sensor Node Communication

Applications of sensor nodes in our daily lives are increasing. Sensor nodes can be embedded in textiles to monitor various environmental parameters or to measure biomarkers. Embedded nodes in fabrics can use wires as means of communication. This approach, however, has drawbacks in terms of reliability, e.g. wire breaks, and discomfort that can arise in a large fabric network with multitudes of cables. Power-line communication (PLC) can mitigate these problems by using conductive planes instead of wires. However, the capacitance formed as a result of using two parallel plates and fabric in between attenuates the signal transmission between sensor nodes. Therefore, in order to compensate the attenuation effect of the conductive fabric which can be achieved by optimizing the hardware, we need to know the capacitance model of the conductive fabric. In our case it is necessary to know the capacitance model as a result of placing a cotton knit fabric between conductive meshes. In this work, we demonstrate that one can use the parallel plate capacitance model for estimating the capacitance of a cotton knit fabric placed between two conductive meshes.