Common Spatio-Time-Frequency Patterns for Motor Imagery-Based Brain Machine Interfaces

Figure 2

Frequency patterns of the spectra of the source signals ((a)–(d)) and the amplitude characteristics of the designed frequency patterns ((e)–(h)). The horizontal axis represents frequency and its unit is Hz.

(a) 1st source, 𝑠₁

(b) 2nd source, 𝑠₂

(c) 3rd source, 𝑠₃

(d) 4th source, 𝑠₄

(e) 1st filter, 𝐡₁

(f) 2nd filter, 𝐡₂

(g) 3rd filter, 𝐡₃

(h) 4th filter, 𝐡₄