SOCM/2 IP/nn Attachment A Bangkok, Thailand 8-10 February 2012

Federal AviationAdministration

Agenda Item 2.2:

Post-Implementation Analysis of Data Link Performance FollowingRelease 15 (R15) Ground Earth Station Software Upgrade

SOCM/2 IP/nnAttachment A

Bangkok, Thailand8-10 February 2012

2Federal AviationAdministration

SOCM/2 IP/nn Attachment ABangkok, Thailand 8-10 February 2012

Contents

Summary of Release 15 GES Upgrade Data Link Performance Analysis of CPDLC and

ADS-C Technical Performance by GES Before = 2 months prior to month in which upgrade

occurred After = 2 months after month in which upgrade occurred Most recent = November/December 2011



Summary of Release 15 GES Upgrade

• Release 15 (R15): Most recent system software upgrade for ground earth stations interfacing with Inmarsat Classic Aero I-3 satellites

• Purpose of upgrade: – To improve GES data link delivery capability and aircraft log-on management

subsystems– To enhance GES traffic handling and monitoring subsystems

GES Identifier and Location Associated DSP Date of R15 Upgrade

XXE – Eik, Norway ARINC 31 January 2010

XXC – Santa Paula, California, USA ARINC 16 February 2010

AOW2 – Aussaguel, France SITA 31 May 2010

POR1 – Perth, Australia SITA 6 July 2010



Data Link Performance Comparison forEik GES (XXE)











Summary of Observed Performance Following R15 Upgrade

• Eik GES:– Improvement in the ACTP was not observed immediately

following the R15 upgrade, but the most recent data does show a noticeable improvement in performance for CPDLC transactions

– ADS-C downlink latency performance is observed to have degraded in the period immediately following the upgrade as well as in the most recent period



Data Link Performance Comparison forSanta Paula GES (XXC)












• Santa Paula GES:– Improvement can be observed for both the ACTP for CPDLC

transactions and ADS-C downlink latency performance for ADS-C downlink messages

– Improvement shown to be stable between the period immediately following the upgrade and the most recent period of observation for both performance measures



Data Link Performance Comparison forAussaguel GES (AOW2)












• Aussaguel GES:– Improvement can be observed for both the ACTP for CPDLC

transactions and ADS-C downlink latency performance for ADS-C downlink messages

– Continued improvement shown between the period immediately following the upgrade and the most recent period of observation for both performance measures



Data Link Performance Comparison forPerth GES (POR1)












• Perth GES:– Slight improvement can be observed for both the ACTP for

CPDLC transactions and ADS-C downlink latency performance for ADS-C downlink messages

– Continued improvement shown between the period immediately following the upgrade and the most recent period of observation for ACTP

– Improvement shown to be stable between the period immediately following the upgrade and the most recent period of observation for the ADS-C downlink latency performance



Conclusions

• Overall improvement in data link performance at GES level following R15 upgrade

• Improvement most noticeable at the Santa Paula and Aussaguel GES

• In general - upgrade appears to have had more of an impact on the ACTP than on the ADS-C downlink latency performance

Documents

SOCM/2 IP/nn Attachment A Bangkok, Thailand 8-10 February 2012