Hardened Tuned-Wall Plastic Radomes for Military Radars
Abstract
XP (stretched polypropylene) film is perhaps the most effective material for construction of hardened dielectric walls. It has excellent fragment-defeat properties, a low relative dielectric constant (2.3) and a very low loss tangent (0.005). For low-loss materials, reflection losses are determined by the dielectric constant and absorption losses by the loss tangent. A perfect radome material would have a dielectric constant of one and a loss tangent of zero. Additionally, XP is self bonding under heat and pressure, allowing construction of homogeneous, tuned-wall design. The wall thickness is chosen to be an integral number of half wavelengths in the material to take advantage of canceling out reflections at the inner wall; loss in beam intensity is then mainly due to absorption in the wall. (1) The resulting thick- wall radome allows efficient r-f transmission and provides a high level of ballistic protection against fragmentation munitions. The AN/TPQ-37 is the first radar antenna considered for hardening against fragment munitions attack.
Document Details
- Document Type
- Technical Report
- Publication Date
- Jan 01, 1976
- Accession Number
- ADA026146
Entities
People
- Anthony L. Alesi
- Eugenio Deluca
- Joseph J. Prifti
Organizations
- United States Army Research Laboratory