Non-invasive brain-computer interface system and coding method with time-varying coding

Abstract

The present invention belongs to the field of brain-computer interface, and for the technical problems that the method in the prior art has high coding difficulty, is difficult to demodulate, and is difficult to adapt to the brain-computer characteristics of users, provides a non-intrusive brain-computer interface coding method of variable-length coding. The method is used for that the human brain sends binary codes which are convenient for the computer to identify to the computer; the human brain generates two first phase signals with a fixed frequency and a fixed stimulation time length, the two first phase signals are respectively corresponding to the binary codes, and a plurality of first phase signals form a symbol; and the interval between the symbols is scaled by changing the time length of the first phase signal in the last bit of the symbol or inserting a coded target. The present invention also discloses a non-intrusive brain-computer interface system of variable-length coding.

Description

technical field [0001] The invention relates to the field of brain-computer interface, in particular to a non-invasive brain-computer interface system and a coding method with time-varying coding. Background technique [0002] Studies have shown that when receiving a fixed frequency of visual stimulation, the visual cortex of the human brain will produce a continuous response related to the stimulation frequency (at the fundamental frequency or double frequency of the stimulation frequency). This response is called Steady-State Visual Evoked Potentials, SSVEP. It can be reliably applied to brain-computer interface systems (BCIs). [0003] In order to receive, detect and analyze SSVEP signals, the prior art provides an FM-SSVEP stimulator system, a steady-state visual stimulator system based on fixed frequencies, which refers to the use of several fixed frequencies as stimulation signals , and then collect the EEG signals when the brain receives these stimuli, perform data ...

AI Technical Summary

Problems solved by technology

[0006] The present invention provides a non-invasive brain-computer interface system with time-varying encoding and an encoding method for the technical problems of difficult encoding, demodulation, and difficulty in adapting to the EEG characteristics of different users in the prior art.

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