A HIGH-TEMPERATURE SUPERCONDUCTIVITY COMMUNICATIONS FLIGHT EXPERIMENT

A high-temperature superconductivity (HTSC) flight experiment from the payload bay of the Space Shuttle Orbiter to the Advanced Communicatio ns Technology Satellite (ACTS) is being breadboarded. This proposed ex periment, a joint project between the Johnson Space Center and the Lew is Research Center, would use a Ka-band (20 GHz) HTSC phased array ant enna and front-end electronics (low-noise amplifier) to receive a down link communications signal from the ACTS. A conventional receiver demo dulates the encoded telemetry signal which is then turned around and t ransmitted back to ACTS and die ground. The HTSC phased array has nine 4 x 4 microstrip patch antenna subarrays which when properly phased, provide approximately 24 dB of boresight gain. A 2 x 2 HTSC microstrip patch has been built and tested. A Ka-band receiver, transmitter, mod em, encoder, decoder, etc., are now being built and tested. Link analy ses and interface problems with the Orbiter are addressed in the paper in addition to the design, fabrication, and testing of various subsys tems used in the communication link.