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1 1 4 
LAN 
KEW KNOWLEDGE ENGINEERING 
ws RTI WORKSTATION 
E SELECTABLE 
[OW IMAGE QUALITY ANALYSIS 
LOE Mais FDDT, ANTENNA WORKSTATION 
SEW SOFTWARE ENGINEERING 
| WORKSTATION 
LAN LOCAL AREA NETWORK 
ST100 CTM 
MEM 1 MWORD MEM 256 MB RTI REAL TIME INPUT 
MFLOPS 100 DMA 40 MB/S 
DMA 100 MB/S DUAL PORT CTM CORNER TURN MEMORY 
ST100 ARRAY PROCESSOR 
COMMANDS 
  
FRONT/END HOST COMPUTER 
e— COMMANDS AND DATA INCLUDING PERIPHERALS 
emu» DMA 
Figure 2. Hardware architecture of ISAR 
2. OBJECTIVES OF THE ISAR MEN-MACHINE-INTERFACE 
Classically the duties of the machine operator include all manual jobs, like 
tape and disk handling or administrative tasks like the generation of 
throughput statistics or taking care of hardware and software maintenance. 
However, if the throughput increases that much, the human operator will not 
be able to operate that fast machines in a reasonable fashion. Due to the 
lack of time he will not be able to react upon malfunction of his machine. 
For example he has in no way a chance to estimate the influence of erroneous 
sensor measurements upon image quality parameters during the time the machine 
generates another product. 
However organizing successfully a SAR processor environment is a much more 
sophisticated task. It is required for the operator to have a fundamental 
knowledge of the SAR processing algorithm, its implementation, the data flow, 
hardware specific features like performance of peripherals (array process- 
ors) or film recorders etc.. The foreseen ERS-1 processing facilities of 
the German PAF (Processing and Archiving Facility) will be designed to have 
a sustained throughput accumulating 6000 products per year. This means that 
each product will be processed in 1/2 hour processing time. However, by 
experience even the remedy of a single malfunction needs now much more time 
than the processor for a whole product. As a result the processor is no 
longer the bottleneck of the production chain and therefore the time behav- 
iour of the overall meh-machine-interface has to be analysed very carefully. 
The following section will give an overview of the most relevant actions at 
the men-machine-interface. It is proposed to group the PAF into several 
functional units, among them are the Data Management Facility and the Pre- 
processor. The Data Management Facility will receive its processing orders 
by satellite and has subsequently to work out all items of concern like 
processing level, required product projection (slant/ground/map), avail- 
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