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Synthetic Aperture Radar

Antenna footprint and resolution, range and cross-range ambiguities, SAR image distortions, SAR image SNR, noise equivalent reflectivity, rain clutter

Model antenna, environment, weather, platform and signal processing gains and losses for synthetic aperture radars. Estimate SAR link budget with the radar range equation. Evaluate scene geometry and hardware constraints on pulse repetition frequency, swath length, area coverage rate, and antenna aperture. Compare ideal and effective resolution of synthetic antenna. Model rain reflectivity for linearly and circularly polarized systems. Model ground reflectivity as a function of surface roughness, operating frequency, polarization and grazing angle.


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aperture2swathSwath extent for radar on ground plane
sarbeamcompratioSAR beam compression ratio
sarbeamwidthSynthetic aperture azimuth beamwidth
sardispgrazangDisplay grazing angle for SAR data collection
sarintangCoherent integration angle for SAR
sarlenSynthetic aperture length
sarmaxswathUpper bound on swath length for SAR
sarmaxcovrateUpper bound on area coverage rate for SAR
sarminapertureLower bound on antenna area for SAR
sarrangeMaximum unambiguous slant range of SAR
sarprfboundsUpper and lower bound on PRF for SAR
sarsquintangSquint angle for SAR data collection
grnd2slantrangeConvert ground range projection to slant range
slant2grndrangeConvert slant range to ground range projection
grnd2slantrngresConvert ground range resolution to slant range resolution
slant2grndrngresConvert slant range resolution to ground range resolution
clutterVolumeRCSRadar cross-section of volume clutter
rainreflectivityVolume reflectivity of rain
rainscrSignal-to-clutter ratio due to rain
radareqsarsnrSignal-to-noise ratio of SAR image
radareqsarpowMinimum peak transmit power using SAR equation
radareqsarrngMaximum detectable range using SAR equation
sarnoisereflNoise equivalent reflectivity of SAR
sarSurfaceRCSRadar cross-section of target for SAR
matchinggainGain due to matched filtering
sarazgainSAR azimuth processing gain
sarchirprateAzimuth chirp rate of received signal for SAR
sarpointdopbwDoppler bandwidth due to cross-range platform motion
sarscenedopbwDoppler bandwidth of full scene after azimuth dechirping
sarinttimeSynthetic aperture integration time
sarprfSynthetic aperture radar PRF
sarazresAzimuth or cross-range resolution for SAR
rainelresElevation resolution of rain limited by radar resolution