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RADARSAT's Beams - Signal Parameters

NOTE: ASF is capable of processing all RADARSAT-1 beam modes to level 0 products. At this time calibrated level 1 data products are only available for standard beams, ScanSAR Wide B, and Fine Beam1. The remaining ScanSAR beams are available as uncalibrated products. NASA approved U.S. investigators may request aquisition of any RADARSAT-1 beam mode through ASF but need to be aware of the processing limitations.

(All beams have HH polarization.)

Avg. PRF Range Bandwidth Sampling Rate Typical Samples per Line
RADARSAT Modes: (Hz) (MHz) (MHz) Real-Time Data
(105 Mbps)		 Recorded Data
(85 Mbps)
Standard Beams:
ST1 1316 17.28 18.467 6350 6350
ST2 1276 17.28 18.467 7292 7292
ST3 1354 11.58 12.927 5942 5942
ST4 1315 11.58 12.927 6356 6356
ST5 1275 11.58 12.927 6702 6702
ST6 1334 11.58 12.927 7146 7146
ST7 1276 11.58 12.927 7646 7646
Wide Beams:
WD1 1270 11.58 12.927 7254 7254
WD2 1310 11.58 12.927 8526 8526
WD3 1350 11.58 12.927 8118 8118
Fine Resolution Beams:
FN1 1300 30.002 32.317 7819 7819
FN2 1270 30.002 32.317 8005 8005
FN3 1330 30.002 32.317 7642 7642
FN4 1315 30.002 32.317 7730 7730
FN5 1300 30.002 32.317 7819 7819
Low Incidence Beams:
EL1 1345 11.58 12.927 7556 7556
High Incidence Beams:
EH1 1345 11.58 12.927 7556 7556
EH2 1307 11.58 12.927 7777 7777
EH3 1270 11.58 12.927 8005 8005
EH4 1245 11.58 12.927 8167 8167
EH5 1307.5 11.58 12.927 7774 7774
EH6 1270 11.58 12.927 8005 8005
ScanSAR Beams:
SWA(SW1):WD1,2,3, ST7 Variable 11.58 12.927 Variable Variable
SWB(SW2):WD1,2, ST5,6 Variable 11.58 12.927 Variable Variable
SNA(SN1):WD1,2 Variable 11.58 12.927 Variable Variable
SNB(SN2):WD2, ST5,6 Variable 11.58 12.927 Variable Variable

Notes:

  1. The Pulse Repetition Frequency (PRF) is given for each beam. The PRF frequencies are about 30 Hz higher for the 792 km altitude.

  2. The range bandwidth is the 3 dB power width of the transmitted radar pulse. The pulse waveform is linear fm ("chirp") and is 40 microseconds long for all three bandwidths. The bandwidths can not be selected for the beams differently from the valve shown in the table.

  3. The sample rates are tied to the chirp bandwidths.

  4. The maximum samples per line are calculated based upon the link rate, overhead data (auxiliary data, chirp replica, and frame overhead), and PRF. A fixed digitization window reduces the actual non-zero pixel values. The window size is set by the highest PRF using the data rate for the recorded mode (85 Mbit/sec). (The CDPF Spec. mentioned a maximum signal line length of 9600.) The numbers are reduced about 3% for the lower altitude due to the higher PRF's.