A TEN-HORN DUAL-FREQUENCY MONOPULSE FEED FOR THE 150-FOOT RANDLE CLIFF RADAR ANTENNA.
Abstract
A ten-horn dual-frequency feed was designed for the 150-foot parabolic antenna of NRL's Randle Cliff Radar. The feed has elevation and azimuth monopulse at 141 MHz and 435 MHz, will transmit 5 kilowatts average and 0.5 megawatts peak power at UHF, and 50 kilowatts average and 5 megawatts peak power at VHF, and uses separate elements for the sum and difference modes. For both frequencies the transmit polarization options are right-hand circular or +45-degree slant linear, and the error horn polarization is linear. The transmit horn will receive left-hand and right-hand circular when right-hand circular is transmitted, and -45-degree and +45-degree slant linear when +45-degree slant linear is transmitted. The feed currently being used in the system has monopulse only at VHF, can transmit only vertical polarization at UHF, and uses the same elements for the sum and difference modes. The design tests were performed on a model of the feed reduced in size by a factor of 3.58. The characteristics measured on the model included VSWR, isolation between transmit horns, isolation between transmit and arror horns, E and H-plane primary patterns, and E and H-plane phase centers. The full scale feed has been built and the UHF system matched prior to installation in the reflector. Because of the greater interaction with the support booms, the VHF system will be matched after the feed is mounted in the reflector. The added features of the new feed will provide new possibilities for missile and space Research. (Author)
Document Details
- Document Type
- Technical Report
- Publication Date
- Apr 01, 1969
- Accession Number
- AD0690862
Entities
People
- William L. Thrift
Organizations
- United States Naval Research Laboratory