1、- 1 - QUESTION ITU-R 73-2/4*Availability and interruptions to traffic on digital paths in the fixed-satellite service (1992-1993-2006) The ITU Radiocommunication Assembly, considering a) that unwanted interruptions, including high-level bursts of noise, occur in satellite links; b) that such interru
2、ptions contribute to unavailability when they exceed 10 consecutive seconds, and are regarded as “short breaks” if they last for shorter periods; c) that the ITU-T and ITU-R objectives for availability and short breaks have a major bearing on the economics of satellite systems; d) that the duration
3、of some interruptions may depend on the configuration of the satellite network; they may also depend on whether earth stations are always attended or unattended at the onset of an interruption, and on whether or not earth station antennas are readily steerable to point from one satellite to another;
4、 e) that Telecommunication Standardization Study Group 13 will continue to provide guidance and interpretation on overall network performance characteristics to Radiocommunication Study Group 4 as it relates to the fixed satellite service, decides that the following Question should be studied 1 What
5、 are the important factors within the satellite portion of hypothetical reference digital paths affecting their availability and short interruptions such as breaks in transmission or bursts of bit errors? 2 What should be the objectives, given the overall network objectives, for satellite radio digi
6、tal path availability for satellite systems which are not included under Recommendation ITU-R S.579? 3 What should be the satellite system objectives, given the overall network objectives, for the duration, distribution, and frequency of occurrence of short breaks in transmission and of short durati
7、on bursts of errors, between points defined by the satellite radio hypothetical reference digital path? further decides that the results of these studies should lead to the formulation of an appropriate Recommendation by 2007. Category: S2 _ *This Question should be drawn to the attention of Telecommunication Standardization Study Group 13.
