The patent badge is an abbreviated version of the USPTO patent document. The patent badge does contain a link to the full patent document.
The patent badge is an abbreviated version of the USPTO patent document. The patent badge covers the following: Patent number, Date patent was issued, Date patent was filed, Title of the patent, Applicant, Inventor, Assignee, Attorney firm, Primary examiner, Assistant examiner, CPCs, and Abstract. The patent badge does contain a link to the full patent document (in Adobe Acrobat format, aka pdf). To download or print any patent click here.
Patent No.:
Date of Patent:
Jun. 02, 1992
Filed:
Jan. 18, 1989
Michael A Grant, Stevenage, GB;
David Robson, Stevenage, GB;
Nicholas F Matthews, Plainboro, NJ (US);
British Aerospace Public Limited Company, London, GB;
Abstract
A multiple access communications system comprises a node spacecraft GEO and several user spacecraft LEO.sub.1 to LEO.sub.n. Each user spacecraft LEO.sub.1 to LEO.sub.n includes a transmit/receive terminal head 18.sub.1 to 18.sub.n, and the node spacecraft GEO includes n transmit/terminals 22 to 22.sub.n and a single beacon unit 24. The beacon beam may be operated to initiate acquisition phases which allow two-way communication to be established between the transmit/receive terminals 22.sub.1 to 22.sub.n on the node spacecraft and the transmit/receive terminals 18.sub.1 to 18.sub.n on the corresponding user terminals. The acquisition phases include a period during which the beacon scans an uncertainty cone associated with the node spacecraft. This scanning period is reduced for second and subseqeunt acquisitions by using the first and subsequently acquired communication links to provide a more accurate estimate of the angular attitude of the node spacecraft, thus reducing the extent of the uncertainty cone.