Contour Analysis of Phase Planes of Quasi-Periodic Biosignals

Two subsystems of living systems were studied as quasi-periodic synchronized processes x 1(t) and x 2(t). The signals were monitored during time interval T, which was determined according to the goals of the tests and the origin of processes. The phase portrait of the system was formed in the framework of references x 1(t) – x 2(t) within the time interval T. The portrait outlook was plotted. Fourier descriptors of the outlook were calculated. The system was classified in the space of Fourier descriptors.