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:
May. 01, 2001
Filed:
Oct. 06, 1997
Marvin R. Wachs, Calabasas, CA (US);
Arnold L. Berman, Los Angeles, CA (US);
Hughes Electronics Corporation, El Segundo, CA (US);
Abstract
A system and method for restricting access to a satellite repeater transponder (,) utilizes a pseudo-random noise generator (,) to automatically modulate a local oscillator (,) about a nominal frequency during frequency translation within the satellite transponder. The carrier signals of authorized user terminals (,) will be modulated with a matching or inverse noise waveform produced by a pseudo-random noise generator (,), so that the noise signal modulated onto the carrier signal will only be cancelled out in authorized transmissions. Thus, an unauthorized user terminal will be unable to recover the baseband signal due to insufficient carrier to noise ratio in the expanded bandwidth created by the pseudo-random frequency modulation in the satellite repeater.