NASA Scientific and Technical Aerospace Reports

solutions. Single and multi-stage pulse tube cryocoolers are currently at the laboratory prototype level. Figure 1 shows the
thermodynamic performance of each cryocooler discussed in this paper.
Author
Cryogenic Cooling; Free-Piston Engines; Prototypes; Thermodynamics
20040068221 NASA Glenn Research Center, Cleveland, OH, USA
Electrical Devices and Circuits for Low Temperature Space Applications
Patterson, R. L.; Hammoud, A.; Dickman, J. E.; Gerber, S.; Elbuluk, M. E.; Overton, E.; International Thermal Detectors
Workshop (TDW 2003); February 2004, pp. 4-11 - 4-15; In English; See also 20040068186; No Copyright; Avail: CASI; A01,
Hardcopy
The environmental temperature in many NASA missions, such as deep space probes and outer planetary exploration, is
significantly below the range for which conventional commercial-off-the-shelf electronics is designed. Presently, spacecraft
operating in the cold environment of such deep space missions carry a large number of radioisotope or other heating units in
order to maintain the surrounding temperature of the onboard electronics at approximately 20 C. Electronic devices and
circuits capable of operation at cryogenic temperatures will not only tolerate the harsh environment of deep space but also will
reduce system size and weight by eliminating or reducing the heating units and their associate structures; thereby reducing
system development cost as well as launch costs. In addition, power electronic circuits designed for operation at low
temperatures are expected to result in more efficient systems than those at room temperature. This improvement results from
better behavior in the electrical and thermal properties of some semiconductor and dielectric materials at low temperatures.
An on-going research and development program on low temperature electronics at the NASA Glenn Research Center focuses
on the development of efficient electrical systems and circuits capable of surviving and exploiting the advantages of low
temperature environments. An overview of the program will be presented in this paper. A description of the low temperature
test facilities along with selected data obtained from in-house component testing will also be discussed. On-going research
activities that are being performed in collaboration with various organizations will also be presented.
Author
Commercial Off-the-Shelf Products; Deep Space; Low Temperature Environments; Low Temperature Tests; Semiconductors
(Materials); Technology Utilization; Test Facilities
20040068223 TRW, Inc., USA
Superconducting Electronics for Detector Readouts
Luine, Jerome; Durand, Dale; Eaton, Larry; International Thermal Detectors Workshop (TDW 2003); February 2004, pp. P1;
In English; See also 20040068186; No Copyright; Abstract Only; Available from CASI only as part of the entire parent
document
Spacecraft subsystems that support thermal detector imaging arrays that operate at temperatures below 80 K can be
benefited by the use of superconducting electronics (SCE). SCE can greatly simplify spacecraft complexity, thereby reducing
costs, and significantly enhance the performance of science instruments and control electronics. For example, by integrating
an analog signal processor and analog-to-digital converter with an imaging sensor array, cryogenic system complexity is
reduced and instrument performance is increased. The number of signal wires leading from the cryogenic detector
environment to higher temperature electronics is reduced thereby reducing cryogenic system complexity. Reduced signal line
count not only simplifies the cryogenic package but also reduces the cryogenic heat load. Cryogenic package simplification
and reduced heat load result in lower cost and increased reliability. Instrument performance is enhanced by executing as much
signal processing at the sensor array as possible. Multiplexing and digitizing the signals in the very low-noise cryogenic
environment increases signal-to-noise ratio. These benefits can also be used to dramatically increase the number of sensor
elements thereby increasing resolution to levels that are extremely difficult or impossible to achieve with today s technology.
Furthermore, materials used for SCE have been found to have orders of magnitude greater radiation hardness than any other
electronics materials. SCE is ideal for cryogenic instruments as well as other spacecraft electronic systems. The status of SCE
technologies for thermal detector readout and signal processing will be presented.
Author
Superconductivity; Signal Processing; Cryogenics; Thermal Mapping; Signal to Noise Ratios
20040068225 Raytheon Co., El Segundo, CA, USA
Integration of Oxford Class Cryocoolers with Thermal Detectors
Kirkconnell, Carl S.; Price, Kenneth D.; International Thermal Detectors Workshop (TDW 2003); February 2004, pp. 6-11
- 6-15; In English; See also 20040068186; No Copyright; Avail: CASI; A01, Hardcopy
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