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:
Feb. 23, 1982
Filed:
Feb. 25, 1980
Timothy P Craig, Georgetown, KY (US);
James R Stimple, Santa Rosa, CA (US);
Paul M Erickson, Schaumburg, IL (US);
Motorola, Inc., Schaumburg, IL (US);
Abstract
A plurality of horizontally directive antenna sectors are arranged in a configuration to receive signals from remote transmitters over a given angle in the horizontal plane. A scanning system is operative in one of several modes to sequentially couple each sector to a receiver. In its first mode, each sector is sequentially scanned with the peak signal level therefrom being compared to a reference level. If the signal level on any sector exceeds the reference level the scanner activates to its second mode wherein scanning of all sectors continues for a predetermined interval after which the system advances to a selective scanning mode wherein scan is limited to that sector with the largest stored signal level relative to the reference level, and to those sectors adjacent said sector for a predetermined time interval. At the end of this interval, scanning is inhibited and the receiver is coupled to that sector which exhibited the strongest relative signal level during the scanning sequences. In this listen mode, if the signal level from the sector falls to a minimum level or a coded squelch is undetected for a given period, the system reverts to the first scanning mode. The system periodically updates the reference levels to account for changes in background noise or the presence of an interfering signal.