1. SPACEBORNE SAR: A HISTORY

2. HISTORY OVERVIEW SAR was invented in 1951/1952 by Carl A. Wiley. Classified research of SAR occurred during the 1950’s and early 1960’s. The first unclassified papers of SAR were published in 1961. This first civilian spaceborne SAR was launched in 1978.

3. SEASAT Launched June 27, 1978 by NASA and JPL Objective: To collect and provide oceanographic data. To provide data for an operational ocean remote sensing system. 42 hours of real time data collected. Seasat did not have any way to record data on the satellite, so data was transmitted in real time to five ground stations. Alaska Satellite Facility has processed the data fully into digital images. Only about 10 percent of the data had been processed digitally. Seasat lasted 106 days at which point the satellite was lost due to a power failure.

4. SEASAT TECHNICAL SPECIFICATIONS

5. JERS-1/FUYO-1 Japanese (JAXA) satellite launched February 11, 1992. Objectives: Generated data sets with SAR and OPS to survey global resources, establishing an integrated Earth observation system, verifying system performances. The applications can be used to survey geological phenomena and various topographical monitoring of the Earth. JERS-1 has a recording time of up to 20 minutes, the capacity is 72 Gbit, then uses QPSK modulation to transmit at a rate of 60 Mbit/s. A malfunction on Oct. 11, 1998 ended the satellites operations. It had stopped being able to record data in August 1997 anyway. The planned lifetime had been 2 years, but it lasted over 6 years.

6. JERS-1/FUYO-1 TECHNICAL SPECIFICATIONS

7. ENVISAT/ASAR Launched March 1, 2002 by the European Space Agency Objectives: Studying the Earth. Applicable disciplines are: meteorology, climatology, environment, atmospheric chemistry, ocean and ice process, and more. Envisat has one tape recorder of 30 Gbit and two SSR of 60 Gbit. The data rate for most of the modes is up to 100 Mbit/s. Loss of contact on April 8, 2012. The mission lasted for 10 years even though only 5 were planned.

8. ENVISAT/ASAR TECHNICAL SPECIFICATIONS

9. RADAR ANALYSIS SatelliteData rateOnboard recording cap. SeasatAnalogNone JERS-160 Mbit/s72 Gbit Envisat100 Mbit/sTotal: 150 Gbit