Toward the development of radiation-tolerant instrumentation data links for thermonuclear fusion experiments

Thermonuclear reactors will require permanent monitoring under high-gamma dose rates and high neutron flux. We propose to get rid of the digital data transmission limitations in highly radioactive environments by implementing an analog fiber-optic link based on directly modulated vertical-cavity surface-emitting laser (VCSELs). In this paper, we introduce an architecture for highly radiation-tolerant instrumentation data links based on the intrinsic wavelength division multiplexing capabilities of fiber-optic data transmission. The potential radiation acceptance level of the analog fiber-optic link is estimated on the basis of irradiation results on individual COTS photonic components such as VCSELs, fiber-optic passive multiplexers, and optical fibers.