THE HIGH-TEMPERATURE SUPERCONDUCTIVITY SPACE EXPERIMENT (HTSSE) - PRESENT STATUS AND FUTURE CHALLENGES

The high-temperature superconductivity space experiment (HTSSE) at the Naval Research Laboratory (NRL) is exploring the feasibility of deplo ying high-temperature superconducting (HTS) electronic devices, compon ents and subsystems in space. The initial HTSSE experiment, which empl oyed HTS technology available in 1990, focused on simple microwave dev ices which were suitably packaged, integrated with a cryogenic refrige rator and built into a space-qualified payload. Unfortunately the HTSS E-1 payload, which was launched in 1993, did not achieve orbit and was lost. The second HTSSE experiment, HTSSE-II, which will use HTS techn ology circa 1993-94, will consist of complex HTS components and hybrid subsystems consisting of HTS and conventional semiconductor component s, the latter operating either at cryogenic temperature or at ambient temperature. The HTSSE-II payload containing the HTS components, cryog enic refrigerator and monitoring electronics will have been built, spa ce qualified and shipped from NRL in November 1995 to the satellite in tegrator for a planned Summer 1996 launch. A description of the HTSSE- II payload will be presented and the performance of the HTS components and their potential impact on future space communications systems wil l be described.