A detection system for measuring one or more conditions within a predetermined area includes a fiber optic cable including a first core for transmitting light to the ambient atmosphere adjacent a node and a second core for receiving scattered light from the ambient atmosphere adjacent the node. A discrimination assembly operably coupled to the first and second cores includes at least one focusing element and at least one optical enhancement device. The at least one optical enhancement device separates the scattered light received from the ambient atmosphere into a plurality of wavelengths. A control system operably coupled to the fiber optic cable receives the scattered light received from the ambient atmosphere. The scattered light received from the ambient atmosphere has a higher frequency than the light transmitted to the ambient atmosphere and only the scattered light having a desired wavelength is transmitted to the control system.