Cross Time-Frequency Analysis for Combining Information of Several Sources: Application to Estimation of Spontaneous Respiratory Rate from Photoplethysmography

Figure 3

(a) Instantaneous frequencies 𝑓_𝑘^𝑖𝑗(𝑡) estimated in Figure 2. (b) Respiratory rate, 𝑓_𝑅(𝑡), and estimated respiratory rate 𝑓_𝑅(𝑡).

(a) Respiration-related component, 𝑓_𝑘^𝑖𝑗(𝑡)

(b) Respiratory rate estimates