A sub-optimum reception of the metal barcode label read by eddy current testing

In this paper, we reduced the estimation of the coil impedance change in reading a metal barcode label with the eddy current testing by introducing the action distance. The inter-bit interference could be seemed additive if the bit interval was larger than the action distance. The sub-optimum reception criterion was investigated under the condition of the additive inter-bit interference where the “sub-optimum” meant that the decision criterion was derived from the probability density function of the additive white Gaussian noise with the inter-bit interference estimation according to the optimum decision criterion.