Accession Number:

ADA230733

Title:

UHF Polarization Characteristics of LES-8/9

Descriptive Note:

Technical rept.

Corporate Author:

MASSACHUSETTS INST OF TECH LEXINGTON LINCOLN LAB

Personal Author(s):

Report Date:

1990-11-07

Pagination or Media Count:

24.0

Abstract:

Lincoln Experimental Satellites 8 and 9 LES-89 were launched together in 1976. On-orbit test made shortly after launch indicated that their UHF communications systems were working properly. In particular, the RHCP characteristics of their UHF antenna systems on orbit were found to be close to those measured before launch. Several years after launch, however, a user of LES-89 UHF functions found discrepancies at some frequencies between the test data and what was expected to be observed, based on RHCP antenna characteristics. Subsequent measurements made at Lincoln Laboratory indicated that the UHF antenna system of LES-8 has changed in its polarization characteristics. It is nearly linearly polarized at some frequencies. A possible cause for this failure has been deduced. So far as is known, LES-9 remains unaffected in this regard. This work was first reported at the Eleventh Meeting of The Technical Cooperation Program TTCP, Subgroup-S Communication Technology and Information Systems, Technical Panel STP-6 Space Communications, held at the Air Force Wright Aeronautical Laboratories, Wright-Patterson AFB, 24-28 October 1983.

Subject Categories:

  • Unmanned Spacecraft

Distribution Statement:

APPROVED FOR PUBLIC RELEASE