Accession Number:

AD0499872

Title:

Removal of Mast Reflections by Harp in the SG Installation Aboard Destroyers,

Descriptive Note:

Corporate Author:

NAVAL RESEARCH LAB WASHINGTON DC

Personal Author(s):

• Wright, R. W.
• Johnson, M. H.

Report Date:

1946-12-22

Pagination or Media Count:

24.0

Abstract:

A study has been made of the antenna patterns for the SG radar installation aboard a destroyer. The relfector and feed were of an improved design with side lobes approximately the same as those of the SG now under development below 30 db. It is shown that side lobes as high as 21 db are introduced by mast reflections and that they may be eliminated by covering the illuminated section of the mast with Harp. The influence of such side lobes on the PPI presentation when large targets are nearby has also been studied and a marked improvement found with the mast reflections removed by Harp. It is concluded that the benefit derived from lower side lobes in an improved SG antenna can only be realized if provision is made to remove the mast reflections by Harp. Author

Descriptors:

• *RADAR CROSS SECTIONS
• *ANTENNA MASTS
• *ANTENNA LOBES
• *ANTIRADAR COATINGS
• MEASUREMENT
• PERFORMANCE(ENGINEERING)
• RADAR IMAGES
• REDUCTION
• ATTENUATION
• ABSORPTION
• REFLECTIVITY
• RADAR ANTENNAS
• SHIP ANTENNAS
• IMPEDANCE MATCHING
• MAGNETRONS
• DESTROYERS
• PLAN POSITION INDICATORS

Subject Categories:

• Electrical and Electronic Equipment
• Structural Engineering and Building Technology
• Active and Passive Radar Detection and Equipment
• Radiofrequency Wave Propagation

Distribution Statement:

APPROVED FOR PUBLIC RELEASE