Detection and matching mechanism for recognition of handwritten letters using WiFi signals

Abstract

The invention discloses a detection and matching mechanism for recognition of handwritten letters using WiFi signals. The invention mainly makes use of the characteristics of wireless signal multipath propagation, and acquires CSI (Channel State Information) data that carry information reflecting external environmental characteristics, including hand movements when letters are written. The CSI data after de-noising (via Butterworth filtering and principal component analysis filtering) show that in the stage of writing letters, the CSI data fluctuate significantly, and the CSI data are relatively stable in the stage without handwriting, and on the basis of the characteristics, the invention provides a waveform feature extraction algorithm to detect and extract waveforms only including information on 26 handwritten letters. Finally, the invention provides a solution combining feature matching and context error correction, takes the waveform as a matching feature, carries out machine learning classification for the extracted 26 feature waveforms, matches the waveforms by using a DTW (dynamic time warping), and improves the recognition accuracy of the system through the context error correction algorithm.

Description

technical field [0001] The invention discloses a detection and matching mechanism for recognizing handwritten letters using WiFi signals, which is mainly used to solve the detection and matching problem of recognizing handwritten letters in a WiFi environment, and involves signal denoising, feature waveform extraction, structure of matching files and Techniques such as contextual error correction. Background technique [0002] Handwritten letters are a natural, intuitive, and easy-to-learn means of human-computer interaction. With the human hand directly used as the input device of the computer, the communication between man and machine will no longer need an intermediate medium. Users can use handwritten letters instead of keyboard input operations, which reduces the difficulty of operation, improves operation efficiency, and promotes the development of human-computer interaction. . In an indoor environment, the radio waves generated by the signal transmitter propagate th...

AI Technical Summary

Problems solved by technology

[0007] [Purpose of the invention]: the present invention mainly solves the problem of identifying handwritten letter information by collecting CSI data in the WiFi environment

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