Study Group XI11 of the ITU-TS has recently approveda new performance recommendation G.826 which theITU-R has recommended as a standard for satellite systemsin recommendation S.1062. G.826 establishes guidelines on theperformance levels of digital systems operating at or aboveprimary rate. These performance levels are stated in terms ofblock error rates. In this paper, we discuss the impact of theblock-based error performance objectives on the performance oftransport systems. However, the impact of G.826 is difficult toevaluate directly since the Performance recommendations are notgiven in terms of bit-error rate (BER) values. Hence, we present aprocedure to convert block error rates to BER. This conversion isbased on the statistical modeling of the error process and includesan analysis of bursty errors as well as random errors. Rather thanusing the equivalent BER values as simple thresholds, we produceBER against time distributions which satisfy G.826 and can beused as masks for a comparison with measured data and also forroute design. It is shown that these masks are a crucial tool in anystudy of G.826 and contain useful information for system designand planning. Indeed it is shown that false conclusions can bedrawn if the masks are not used. Finally, the impact of G.826 isdiscussed with particular reference to apportionment strategies,system margins, signal processing, and error correction schemes.
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