Skip to main content
U.S. Department of Energy
Office of Scientific and Technical Information

Ultra-wideband VHF SAR -- Design and measurements

Conference ·
OSTI ID:207932
; ; ; ; ;  [1]; ; ;  [2]
  1. National Defense Research Establishment, Linkoeping (Sweden)
  2. Massachusetts Inst. of Technology, Lexington, MA (United States)

CARABAS, an acronym for ``Coherent All Radio Band Sensing``, is an airborne, horizontal-polarization SAR operating across the frequency band 20--90 MHz, conceived, designed and built by FOA in Sweden. The original motivation for designing such a low frequency system was that a large relative or fractional bandwidth could be achieved at low frequencies. For reasons to be explained, a large fractional bandwidth was considered to be of potential benefit for radar detection in severe clutter environments. A feasibility study of a short wave ultra-wideband radar started at FOA in 1985. Actual construction of the CARABAS system commenced 1987, aircraft integration took place during 1991 and the first radar tests were conducted in early 1992. From the fall of 1992 onwards, field campaigns and evaluation studies have been conducted as a joint effort between FOA and MIT Lincoln Laboratory in the US. This article will focus on experiences concerning foliage penetration with the system. First the authors touch upon the CARABAS system characteristics, outline the arguments behind a large-fractional-bandwidth VHF-band SAR approach to foliage penetration, and finally present some early experimental results. The authors refer to other papers, for a fuller explanation of the system, for more details of image calibration and for results concerning underground imaging.

OSTI ID:
207932
Report Number(s):
CONF-940449--; ISBN 0-8194-1521-9
Country of Publication:
United States
Language:
English

Similar Records

Measurements of ionospheric effects on wideband signals at VHF
Technical Report · Mon Aug 17 00:00:00 EDT 1998 · OSTI ID:334342

CARABAS - an airborne VHF SAR system
Conference · Thu Oct 31 23:00:00 EST 1996 · OSTI ID:390846

Ionospheric effects on synthetic aperture radar at VHF
Conference · Fri Jan 31 23:00:00 EST 1997 · OSTI ID:460790