LF TO VHF SHIPBOARD DIRECTION FINDING RESEARCH

The DF performance of the ferrite core crossed spaced loop antenna at the SwRI full-scale superstructure site showed calibration curves equivalent to the air core spaced loop previously tested. This included 2:1 reradiation error reduction compared to a simple loop and the elimination of multivalued and no bearing calibration curves. A five- element phase measuring interferometer was operated on the ship superstructure site using crossed simple loop antenna elements with sensitivity in excess of 20 microvolts/m at 2 MHz with commensurate improvement above 2 MHz. Baseline lengths employed were 270 x 105 ft. Azimuth and elevation calculations on skywave and ground wave targets were performed in real time using an on-line digital computer. DF errors averaged less than plus or minus 5 deg. over the bearing circle with the exception of narrow angular sections in the loop null regions. These can be eliminated by omnidirectional loop antennas. The SwRI direction finding calibrator was used with an on-line computer to provide automatic bearing corrector capability with a polar CRT direction finder display. ( Author )

• Corporate Authors:

  Southwest Research Institute

  6220 Culebra Road, P.O. Drawer 28510
  San Antonio, TX  United States  78228-0510
• Authors:
  • Green, T C
  • Sherrill, W M
  • Lorenz, R
• Publication Date: 1970-3-2

Media Info

• Pagination: 55 p.

Subject/Index Terms

• TRT Terms: Radio direction finders; Radio navigation
• Uncontrolled Terms: Direction finding
• Subject Areas: Marine Transportation; Operations and Traffic Management;

Filing Info

• Accession Number: 00007006
• Record Type: Publication
• Source Agency: National Technical Information Service
• Files: TRIS
• Created Date: Nov 25 1970 12:00AM