Accession Number : ADD006350

Title :   Configuration of Two Antennae with Signal Isolation.

Descriptive Note : Patent,


Personal Author(s) : Weber,John W

Report Date : 10 Apr 1979

Pagination or Media Count : 9

Abstract : The configuration consists of two antennae on the same mast. The upper antenna is a ground plane capable of two frequency bands of operation. The lower antenna comprises a sleeve and radial elements. The upper antenna consists of four radials 36 in. long and an upper element. The two bands of operation covered by the upper antenna are 80 MHz and 150 MHz. Band selection is accomplished by selection of the correct upper mast element. This element is removable. A 34in. long element is used for 80 MHz operation and a 14 in. long element for 150 MHz operation. This antenna is nondirectional and is used for transmitting. The lower antenna consists of four radials 22 in. long and an upper and lower sleeve. The radials are insulated from the mast and connected to the center conductor of the coax. The upper sleeve is a portion of this antenna and also isolates the antenna from the mast. The only use of the lower sleeve is to provide isolation of the antenna from the mast and coaxial cable. This antenna is nondirectional and used for receiving at 140 MHz. The upper and lower antenna are isolated by 20 dB. (Author)

Descriptors :   *Patents, *Antenna configurations, Duplexers, Dual channel

Subject Categories : Electrical and Electronic Equipment
      Radio Communications

Distribution Statement : APPROVED FOR PUBLIC RELEASE