ABSTRACT
Brain-computer interface (BCI) is technology to provide direct control of devices without the participation of peripheral nervous system and muscles [1]. It is first described in 1973 [2], and get great development since 1993 [3]. Currently, more and more researches have been done in this field. Generally, there are three methods to extract signals from the brain: invasive [4], half-invasive [5], and non-invasive [6].
