Vital sign monitoring device and method

The invention relates to a vital sign monitoring device and method, belongs to the technical field of vital sign monitoring, and solves the problems in the prior art. The device comprises a pulse light source used for generating a first optical pulse signal; the first optical pulse signal circulates for multiple times in the optical fiber annular cavity and is continuously attenuated, a fiber grid structure is laid below a first optical fiber part of the optical fiber annular cavity to form a micro-bend optical fiber sensor, and the BCG signal acts on the micro-bend optical fiber sensor to enable the fading time of a second optical pulse signal output by the optical fiber annular cavity to change; the photoelectric detector is used for converting the second optical pulse signal into an electric signal; the digital signal processing circuit is used for calculating the fading time of the optical fiber annular cavity according to the electric signal so as to obtain a BCG signal, and then vital sign information i