Modular Architecture for the Measurement of Space Radiation
- Created: Friday, 01 June 2007
New architecture developed with improved capabilities adds radiation hardness.
A modular architecture has been conceived for the design of radiation-monitoring instruments used aboard spacecraft and in planetary-exploration settings. This architecture reflects lessons learned from experience with prior radiation-monitoring instruments. A prototype instrument that embodies the architecture has been developed as part of the Mars Advanced Radiation Acquisition (MARA) project. The architecture is also applicable on Earth for radiation-monitoring instruments in research of energetic electrically charged particles and instruments monitoring radiation for purposes of safety, military defense, and detection of hidden nuclear devices and materials.
The present architecture as embodied in the MARA instrument design offers the following advantages over the architectures and designs of prior radiation-monitoring systems:
The detector interface circuitry in prior instruments included voltage-feedback operational amplifiers, which do not enable accurate tracking of the rising edges of incoming pulses and, as a result, do not enable deterministic discrimination among different levels of radiation events. In contrast, the MARA circuit design provides the capability to more accurately differentiate among different types of energetic charged particles.
Unlike prior designs, the MARA design provides for correlated double sampling, which offers the advantage of subtraction of correlated noise between reset samples and data samples, thereby reducing spurious offsets and the effects of low-frequency noise.