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SweepSAR: Beam-forming on Receive Using a Reflector-Phased Array Feed Combination for Spaceborne SARIn this paper, an alternative approach is described that is suited for longer wavelength SARs in particular, employing a large, deployable reflector antenna and a much simpler phased array feed. To illuminate a wide swath, a substantial fraction of the phased array feed is excited on transmit to sub-illuminate the reflector. Shorter transmit pulses are required than for conventional SAR. On receive, a much smaller portion of the phased array feed is used to collect the return echo, so that a greater portion of the reflector antenna area is used. The locus of the portion of the phased array used on receive is adjusted using an analog beam steering network, to 'sweep' the receive beam(s) across the illuminated swath, tracking the return echo. This is similar in some respects to the whiskbroom approach to optical sensors, hence the name: SweepSAR.SweepSAR has advantages over conventional SAR in that it requires less transmit power, and if the receive beam is narrow enough, it is relatively immune to range ambiguities. Compared to direct radiating arrays with digital beam- forming, it is much simpler to implement, uses currently available technologies, is better suited for longer wavelength systems, and does not require extremely high data rates or onboard processing.
Document ID
20130010590
Acquisition Source
Jet Propulsion Laboratory
Document Type
Conference Paper
External Source(s)
Authors
Freeman, A.
(Jet Propulsion Lab., California Inst. of Tech. Pasadena, CA, United States)
Krieger, G.
(Deutsche Forschungsanstalt fuer Luft- und Raumfahrt Wessling, Germany)
Rosen, P.
(Jet Propulsion Lab., California Inst. of Tech. Pasadena, CA, United States)
Younis, M.
(Deutsche Forschungsanstalt fuer Luft- und Raumfahrt Wessling, Germany)
Johnson, W. T. K.
(Jet Propulsion Lab., California Inst. of Tech. Pasadena, CA, United States)
Huber, S.
(Deutsche Forschungsanstalt fuer Luft- und Raumfahrt Wessling, Germany)
Jordan, R.
(Jet Propulsion Lab., California Inst. of Tech. Pasadena, CA, United States)
Moreira, A.
(Deutsche Forschungsanstalt fuer Luft- und Raumfahrt Wessling, Germany)
Date Acquired
August 27, 2013
Publication Date
May 4, 2012
Subject Category
Communications And Radar
Meeting Information
Meeting: RadarCon
Location: Pasadena, CA
Country: United States
Start Date: May 4, 2012
Distribution Limits
Public
Copyright
Other
Keywords
synthetic aperture radars (SARs)
phased array
return echo

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