AIRSAR Single Channel Survey Product Description

The survey product is an overview of all the data contained on a High Density Digital Cassette (HDDC) and provides sufficient information for designating data to be processed at full resolution. The prints show all the data on the HDDC, and may include calibration data, baseline tests, and other non-image data. An example is attached and the format described below.

Run Name: geographic description of the area being imaged, followed by a number indicating the aircraft azimuth heading and a serial number indicating the number of the flight line along that heading. MissionRange049-1 indicates the first run along a 49° heading over the Mission Range site. Run names are unique for a given flight day, but may be repeated on other days.

Flight Date: indicates the year/month/day of data collection

HDDC ID: indicates the HDDC that contains the raw flight data

Radar Mode: indicates the AIRSAR mode of data collection (see description below)

 Definition of AIRSAR Radar Modes
Polsar: P- , L- , and C-band polarimetry (HH, HV, VH, VV polarizations)

Topsar Modes

ATI*: L- and C-band double-baseline along track interferometry in VV polarization only

XTI1: C-band single baseline cross track interferometry in VV polarization only

XTI1P: C-band double baseline cross track interferometry in VV polarization only; L- and P-band polarimetry

XTI2*: L- and C-band single baseline cross track interferometry in VV polarization only; P-band polarimetry

XTI2P*: L- and C-band double baseline cross track interferometry in VV polarization; P-band polarimetry

 

 Chirp Bandwidth: indicates the bandwidth during data collection

Radar Altitude: indicates the altitude of the radar during data collection.

Swath Width: indicates the cross track width of the collected data swath. Note that the swath width of the final precision data products may be smaller if the signal-to-noise ratio (SNR) is low towards the swath edges.

Flight Direction and Illumination: these arrows show the flight path, the AIRSAR radar system looks left of the flight path.

Radar Channel: the survey photo product shows a single frequency and polarization, usually L-band horizontal transmit, horizontal receive (LHH), out of the twelve frequency/polarization combinations that are normally recorded.

Incidence Angles: the numbers across the top of the image indicate the incidence angles across the swath.

Left Margin Annotation: five parameters given are for the tick marks along the left edge of the image.

Yaw Angle of the aircraft during data collection.

Swath Center Latitude and Longitude - this is approximate.

Greenwich Mean Time (GMT) of data collection

Frame Count - 6 or 7 digit number is the key to specifying data to be processed at full resolution. Numbers are printed every ~20,000 frame counts. For POLSAR data ~40000 frame counts = 10 km; for TOPSAR data ~42000 frame counts = 10 km. To specify data for standard processing, please read the instructions on the back of the processing request form.

 Survey data may contain significant azimuth ambiguities, appearing as "ghost" images or an apparent doubling of image features. These ambiguities result from the simple algorithm used for survey processing, and the effect will not be present in the frame processed data which is processed with motion compensation of the aircraft. Also, image brightness and contrast may vary from run to run, even over the same type of terrain. For these reasons, the survey data should not be used for any scientific analysis or interpretation. Even comparing images of the same area from two different days may be quite misleading.