Abstract：In near-infrared non-invasive blood glucose measurement, the signal variation caused by glucose is very weak, vulnerable to human involvement, measuring instruments and environmental changes, limiting the accuracy of non-invasive blood glucose sensing. To address this issue, the group applies the theory of floating reference position to eliminate background interference.However, due to the individual differences and the complexity of human environment, the floating reference positions will vary from person to person.Based on the Monte Carlo simulation of three layer skin model of human palm, the floating reference positions of 1 000~1 700 nm near infrared band were found in the vicinity of 2 mm of the radial distance from the light source.So in order to improve the applicability of the floating reference methods in different persons, this paper presents a near floating reference measuring(N-FRM) method. The radial distance 2 mm was chosen as the reference position for background interference’s correction, then the effect by phantom experiments is validated. Furthermore select the phantom Intralipid solution with 2% and 3% concentration for experiments, whose floating reference positions are close to the skin model of human palm. The results showed that the N-FRM method could reduce the influence of light source drift, improve the repeatability and stability of data. Based on multiple diffuse reflection signal acquisition of 2% and 3% intralipid solutions with different glucose content and the glucose concentration prediction models, and it was found that the regression models' root mean square errors of prediction were reduced by 38.51%~79.98% and 29.72%~52.22%. The comparison showed that this method could effectively eliminate the common background changes at two measured positions,improve the prediction accuracy of the calibration models. The results of phantom experiments provide a strong support for the application of N-FRM’s in vivo measurement.
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