This work proposes a highly sensitive sandwich heterostructure multimode optical fiber microbend sensor for heart rate (HR), respiratory rate (RR), and ballistocardiography (BCG) monitoring, which is fabricated by combining a sandwich heterostructure multimode fiber Mach–Zehnder. This work proposes a highly sensitive sandwich heterostructure multimode optical fiber microbend sensor for heart rate (HR), respiratory rate (RR), and ballistocardiography (BCG) monitoring, which is fabricated by combining a sandwich heterostructure multimode fiber Mach–Zehnder. Microbend sensors represent a fascinating and versatile class of fiber optic sensors. They are designed to detect and quantify physical parameters like pressure, displacement, and vibration by monitoring changes in the light transmission characteristics of an optical fiber subjected to controlled. s synonymous with optical telecommunication. Another useful dimension of fiber optics is that it has also provided a revolutionary technology base for configuring a variety of optical sensors, which offer several advantages their small size and mechanical flexibility. According to the measured refractive. Intensity modulation induced by microbending in multimode fibers is considered as a transduction mechanism for detecting environmental changes such as pressure, temperature, acceleration, and magnetic and electric fields. A generic microbend sensor has been defined and studied, and its components.
