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:
Nov. 24, 1992
Filed:
Oct. 30, 1990
John E Hershey, Ballston lake, NY (US);
Amer A Hassan, Clifton, NY (US);
Charles M Puckette, Scotia, NY (US);
General Electric Company, Schenectady, NY (US);
Abstract
A countermeasure to a partial-band follower jammer for frequency hopping spread spectrum communication systems employs an M-ary orthogonal frequency shift keyed (FSK) signaling system having q frequency channels available for hopping. During each signaling interval, the transmitter and receiver operate in either a conventional or unconventional mode. The conventional mode is selected by the transmitter and the receiver with a pseudorandom probability p.sub.c. In this mode, the transmitter transmits one of r tones within the corresponding hop (i.e., within one of q channels), and log.sub.2 r information bits are conveyed, while the receiver comprises a dehopper followed by noncoherent matched filters. The unconventional mode is selected with probability 1-p.sub.c. In this mode, the transmitter randomly chooses one of the r tones and transmits it in one of r channels within each hop, where the r channels are selected pseudorandomly. In the unconventional mode, log.sub.2 r information bits are transmitted and the receiver comprises a bank of r radiometers.