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Hand Gesture Recognition Based on Ultrasound Technology: Pre-processing Stage

This paper describes an approach, which can be used as a pre-processing stage for a hand detection and gesture recognition problem. The approach is based on noise cancellation using QRD Recursive Least Squares (RLS) algorithm with double precision arithmetic and exponential forgetting (EF). The paper discusses algorithmic techniques and presents experiments showing how it is possible to calculate the distance between a hand and a device. A series of experiments were performed. During them a time-variant environment regression model and a time-variant hand model as well as different values of the EF factor were used.