The sensor consists of a fiber splitter with the configuration of one input to multiple fiber outputs, i. 1×4, 1×8 and 1×12 arrangements that act as a discrete liquid level. A broadband source (BBS) is used as the light source supply. This work reports an optical fiber–based continuous liquid level sensor for cryogenic propellant mass gauging, which has significant advantages over the existing liquid level sensors in terms of accuracy, simplicity, and reliability. Additionally. als in industrial and processing plants. 2–17 Liquid level sensors can be classified into two main cat-egories: continuous evel sensors and discrete level sensors. The total reflected power intensity is measured using a power.