1. WGM 8 meeting / 24-28 November 2003 1 EUROCONTROL VDL Mode 4 Airborne Architecture Study (VM4AAS) Study Overview and Conclusions Nikos Fistas EATMP / EUROCONTROL Communications & Surveillance Management ACP WG-M/8 Appendix J

2. WGM 8 meeting / 24-28 November 2003 2 EUROCONTROL Presentation Overview PART I: General information Scope, Objectives, Plan, Structure PART II: Study Summary Overview of work achieved (Work Packages 1 to 4) Conclusions Recommendations Next Steps

3. WGM 8 meeting / 24-28 November 2003 3 EUROCONTROL PART I: GENERAL INFORMATION

4. WGM 8 meeting / 24-28 November 2003 4 EUROCONTROL VM4AAS scope Investigate airborne integration issues for VDL Mode 4, considering: COM / SUR / COM and SUR applications Large / Small / Light a/c Forward-fit / Retrofit (digital and analogue) a/c

5. WGM 8 meeting / 24-28 November 2003 5 EUROCONTROL VM4AAS Objectives (contd) To provide answers to questions identify potential problems make recommendations contribute to decision making provide input/guidance to manufacturers considering current status and future trends

6. WGM 8 meeting / 24-28 November 2003 6 EUROCONTROL Study Background Information ( Performed by Honeywell ( Started in June 2002 ( Finished October 2003 ( Informal external review group (open to interested volunteers )

7. WGM 8 meeting / 24-28 November 2003 7 EUROCONTROL D1 WP1.3 Definitions, Assumptions and Baselines WP1.3 Definitions, Assumptions and Baselines WP3.2 Radio Frequency Interference D3.2 WP2.2 Architecture Requirements & Constraints WP2.1 Applications Data Requirements WP2.2 Architecture Requirements & Constraints WP2.1 Applications Data Requirements D2 WP3.1 Avionics Architectures WP3.1 Avionics Architectures D3.1 WP4 Implementation Plan WP5 Draft Final Report WP4 Implementation Plan 29/10/03 VM4 Airborne Integration Meeting VM4AAS Deliverables WP4 Implementation Plan WP4 Implementation and Transition D4 WP4 Implementation Plan WP5 Final Report

8. WGM 8 meeting / 24-28 November 2003 8 EUROCONTROL Deliverable Review Process Final Deliverable on Web Final Deliverable on Web Comment Resolutions on Web Comment Resolutions on Web External Review group (volunteers) Airbus Avtech Sweden British Airways Boeing CNSS Dittel EasyJet PMEI Rockwell-Collins SAS SCAA Honeywell/ EUROCONTROL Resolution External Draft Deliverable Internal Draft Deliverable Honeywell/ EUROCONTROL Resolution EUROCONTROL Review

9. WGM 8 meeting / 24-28 November 2003 9 EUROCONTROL PART II STUDY SUMMARY

10. WGM 8 meeting / 24-28 November 2003 10 EUROCONTROL VM4AAS Work Structure Preparatory work WP1 - D1:Assumptions and Baselines WP2 - D2:Identifications of Requirements Investigations WP3 - D3.2: RF Interference Analysis WP3 - D3.1: Avionics Architectures WP4 - D4:Implementation and Transition

11. WGM 8 meeting / 24-28 November 2003 11 EUROCONTROL Work Package 1: Assumptions and Baselines Preliminary work to form the foundations WP3 Establish assumptions Establish baselines

12. WGM 8 meeting / 24-28 November 2003 12 EUROCONTROL WP1: Assumptions VDL Mode 4 is acceptable to support applications CDL only SDL only combined CDL and SDL 15 other assumptions in 3 broad groups Group 1: SSR Mode-S-based ACAS Group 2: Simultaneous VHF Communications Group 3: 8.33 kHz VHF Voice will be required throughout the study period

13. WGM 8 meeting / 24-28 November 2003 13 EUROCONTROL WP1: Aircraft Classes Large: take-off mass >15,000 kg (Citation X, G-IV, ERJ, Airbus, Boeing) Small: 5700 kg < take-off mass < 15,000 kg (King Air 350, most Citation) Light: take-off mass < 5700 kg (Cessna 172, King Air C90B)

14. WGM 8 meeting / 24-28 November 2003 14 EUROCONTROL WP1: Equipment Baselines (1) Communication VHF Voice (DSB-AM) x 2 ACARS or Mode 2 Simultaneous operation of voice and data link Navigation GNSS ILS (Localizer and Glideslope) VOR

15. WGM 8 meeting / 24-28 November 2003 15 EUROCONTROL WP1: Equipment Baselines (2) Surveillance Mode S Transponder #1 Mode S Transponder #2 or Mode C ACAS Mode S Interrogator (Large & Small) CDTI

16. WGM 8 meeting / 24-28 November 2003 16 EUROCONTROL Work Package 2: Identification of Requirements ( Identify general functional requirements ( Identify internal interfaces ( Identify external interfaces

17. WGM 8 meeting / 24-28 November 2003 17 EUROCONTROL WP2: Internal Interfaces ( Interconnections VDLM4 to and from other avionics ( Data Flow Diagrams ( Data Dictionary ( Precision Time Interface (PTI) CONCLUSION: Only PTI and baseband interface issues are unique to VDL Mode 4 compared to any other CDL/SDL modem technology

18. WGM 8 meeting / 24-28 November 2003 18 EUROCONTROL WP2: Context-Level DFD An example: Level 1 - external interactions

19. WGM 8 meeting / 24-28 November 2003 19 EUROCONTROL WP2: External Interface Issues ( RF Interference to/from other avionics ( Focus on same-aircraft or co-site problems ( Detailed study in WP3.2 ( Derived work on integrity, availability, and continuity of service ( Traffic Loading estimates for 2015 based on MACONDO

20. WGM 8 meeting / 24-28 November 2003 20 EUROCONTROL Work Package 3.2: Interference Analysis (1) ( RF Interference Issues ( VHF Communications Sources: DSB-AM, VDL Mode 2, VDL Mode 4 Communication Victims: DSB-AM, VDL Mode 4, VDL Mode 2 Navigation Victims: Localizer, VOR, VDB, Glideslope ( Large, Small, Light Aircraft

21. WGM 8 meeting / 24-28 November 2003 21 EUROCONTROL Work Package 3.2: Interference Analysis (2) ( Same-side, Opposite-side antennas ( Link-budget analysis using published standards or carefully documented assumptions ( 3 issues: Desensitization, Off-Channel Emissions, RF (front end) Saturation

22. WGM 8 meeting / 24-28 November 2003 22 EUROCONTROL WP3.2: VHF COM I/f Problem -180 -140 -100 -60 -20 +20 Power Spectral Density dBm/Hz thermal noise minimum signal level receiver noise floor thermal noise reference signal level minimum digital transmitter output (16 W = +42 dBm) -98 dBm -87 dBm -98 dBm +129 dB (!) -40 dB

23. WGM 8 meeting / 24-28 November 2003 23 EUROCONTROL WP3.2: Key Assumptions MOPS -87 dBm reference signal level Emissions levels DO-186A (Voice), DO-281/ED-92 (Mode 2), ED108 (Mode 4) Assumed noise floors Using ARINC 716 isolations MOPS adjacent channel rejection ACR is a desensitization spec Figure of merit Es/N0 or S/P

24. WGM 8 meeting / 24-28 November 2003 24 EUROCONTROL WP3.2: 3 VHF-on-VHF i/f scenarios Voice on digital RF Saturation IF Desensitization Off-channel emissions (residual phase noise) Digital on voice RF Saturation Squelch break Audio S/P concerns Digital on digital RF Saturation Desensitization IF Off-Channel emissions (residual phase noise)

25. WGM 8 meeting / 24-28 November 2003 25 EUROCONTROL WP3.2: Voice on digital i/f Mechanism Primarily phase noise and RF saturation IF desensitization is lesser effect Challenges 100% voice duty factor Mitigations Better in-band filtering for digital receiver (IF) Better-than-MOPS phase noise of voice transmitter Increased isolation Channel separation Robust application protocols Clear continuity definitions Reduced use of AM voice as data use increases

26. WGM 8 meeting / 24-28 November 2003 26 EUROCONTROL WP3.2: Digital on voice i/f Mechanism Primarily phase noise and RF saturation IF desensitization is lesser effect Challenges Better than MOPS sensitivity of most AT voice receivers Mitigations Better than MOPS emissions for digital transmitter Increased isolation Channel separation Constrain protocols to short pulse widths (adverse impact on clicks) Consider cooperative suppression during transmissions

27. WGM 8 meeting / 24-28 November 2003 27 EUROCONTROL WP3.2: Digital on digital i/f Mechanism Primarily phase noise and RF saturation IF desensitization is lesser effect Challenges Multiplicity of antennas/limited isolation Low-noise figure designs with FM protection Mitigations Better emissions for digital transmitter Better-than-MOPS adjacent channel rejection Increased isolation Channel separation Robust applications and protocols Clear continuity definitions

28. WGM 8 meeting / 24-28 November 2003 28 EUROCONTROL WP3.2: Off-channel & Desensitization Required frequency separations in (KHz) to solve the interference problem (additional analysis is being finalised)

29. WGM 8 meeting / 24-28 November 2003 29 EUROCONTROL Certain: In band signal > +10 dBm and within ~3 MHz Very Probable: In band signal >-10 dBm and within ~3 MHz Probable: In band signal >-25 dBm and within ~3 MHz Possible: In band signal >-33 dBm (MOPS Specification) None: In band signal <-33 dBm (MOPS Specification) WP3.2: RF Saturation ( New result (not in original WP3.2) ( Supported by Boeing/Honeywell testing (Sept 2003 - data not yet released) ( May be the limiting factor!

30. WGM 8 meeting / 24-28 November 2003 30 EUROCONTROL Work Package 3.1: Architecture Descriptions 11 different forward fit architectures 1 radio retrofit architecture Recommendations Multi-function VHF radio 8.33 kHz, 25 kHz, VDLm2, VDLm4 Independent transmit and receive capabilities Baseband control and flexibility

31. WGM 8 meeting / 24-28 November 2003 31 EUROCONTROL WP3.1: requirements and constraints Integrity RMER 10 -6 to 10 -8 Continuity Loss of Continuity 1 x 10 -5 to 5 x 10 -4 Availability Communication system MTBF 1000 days Surveillance system MTBF 1000 day

32. WGM 8 meeting / 24-28 November 2003 32 EUROCONTROL WP3.1: Architecture Candidate #5 ( ARINC 750 form factor New VHF Digital Radio (NVDR) ( 4R1T, half duplex transceivers (not available today) ( High-speed baseband information sharing ( Independently reconfigurable R/T capabilities

33. WGM 8 meeting / 24-28 November 2003 33 EUROCONTROL WP3.1: Architecture Candidate #9 ( Remote mount high-end B/RA New VHF Digital Radio (NVDR) ( 4R1T, half duplex transceivers (not available today) ( High-speed baseband information sharing ( Independently reconfigurable R/T capabilities

34. WGM 8 meeting / 24-28 November 2003 34 EUROCONTROL WP3.1: Architecture Candidate #10 ( Retains existing analog voice radio for GA aircraft ( Small form factor (panel mount?) NVDR ( 4R1T, half duplex transceivers (not available today) ( Independently reconfigurable R/T capabilities ( Somewhat limited under certain failure conditions

35. WGM 8 meeting / 24-28 November 2003 35 EUROCONTROL WP3.1: Architecture Candidate #11 ( Retains existing analog voice radio for GA aircraft ( Small form factor (panel mount?) NVDR ( 4R1T, half duplex transceivers (not available today) ( Independently reconfigurable R/T capabilities ( Somewhat limited under certain failure conditions

36. WGM 8 meeting / 24-28 November 2003 36 EUROCONTROL WP3.1: Other Products ( Allocation table showing how each transmitter and receiver is used ( Availability/continuity analysis tables ( Analytical Appendices

37. WGM 8 meeting / 24-28 November 2003 37 EUROCONTROL Work Package 4: Implementation and Transition ( Relative normalized costs of installation in a variety of configurations ( Typical and Best-Case schedules

38. WGM 8 meeting / 24-28 November 2003 38 EUROCONTROL WP4: Summary of Relative Costs

39. WGM 8 meeting / 24-28 November 2003 39 EUROCONTROL WP4: Serial Task Schedule

40. WGM 8 meeting / 24-28 November 2003 40 EUROCONTROL WP4: Aggressive Schedule

41. WGM 8 meeting / 24-28 November 2003 41 EUROCONTROL Work Package 5: Final Report & Summary Summarize WPs 1, 2, 3.2, 3.1, and 4 Review external comments Conclusions Recommendations Open Items and Future Work

42. WGM 8 meeting / 24-28 November 2003 42 EUROCONTROL WP5: Review of External Comments ( Comments critical of WP 3.2 VHF Voice assumptions were too severe Worst-case and not statistical analysis Not supported by field data and/or trial experience ( Comments about cost analysis with lack of benefit analysis ( Comments about intermodulation ( Comments about saturation

43. WGM 8 meeting / 24-28 November 2003 43 EUROCONTROL WP5: Study Conclusions (1) Interference Problem: ( VHF-on-VHF interference will exist ( VHF-on-VHF interference may prevent simultaneous voice and data usage provided by separate systems (valid for all VDLs) ( Voice-on-VDL interference is more critical ( Only half-duplex is achievable ( Uplink data applications must be made sufficiently robust to sustain transfer delay due to downlink voice ( Technical mitigations seem insufficient

44. WGM 8 meeting / 24-28 November 2003 44 EUROCONTROL WP5: Study Conclusions (2) Aircraft Integration Problem: ( Recommended architectures are based on multi-function half-duplex VHF transceiver with 1 TX and 4 RXs ( Recommended architectures require interconnected transceivers ( VDL Mode 4 specific integration issues limited to PTI and baseband connections

45. WGM 8 meeting / 24-28 November 2003 45 EUROCONTROL WP5: Study Conclusions (3) General VDL Mode 4 installation plans should be coordinated with ADS-B and/or advanced data link upgrades Simultaneous operation of multiple VDLs and voice should be avoided

46. WGM 8 meeting / 24-28 November 2003 46 EUROCONTROL WP5: Study Recommendations ( Investigate operational impact of VDL Mode 4 interference to voice and vice versa to determine if and which applications can be supported ( Complete feasibility analysis (safety,..) of recommended architectures and facilitate as appropriate the development of multi-function 4R1T transceiver with 8.33/25 kHz analog voice, VDL Mode 2, VDL Mode 4 common baseband coordination quasi-independent R/T functions ( Use VMAAS results as input to other efforts to complete VDL Mode 4 specific cost/benefit analysis (CBA) to support link decision ( Coordinate any aircraft upgrades with ADS-B and advanced CDL application upgrades

47. WGM 8 meeting / 24-28 November 2003 47 EUROCONTROL WP5: Open Items/Future Work (1) ( Assess operational impact of voice-on-data interference ( Adopt GFSK BER analysis as part of a standard for reference ( Adopt VDL Mode 4 link budget to level of detail comparable with other VDL data links

48. WGM 8 meeting / 24-28 November 2003 48 EUROCONTROL WP5: Open Items/Future Work (2) ( Perform or refine system-level cost benefit analysis based on relative costs provided by WP4 ( Perform, publish, and publicize additional measurements of VHF-on-VHF interference effects

49. WGM 8 meeting / 24-28 November 2003 49 EUROCONTROL VM4AAS Remarks & Questions More info and available draft deliverables: www.eurocontrol.int/vdl4/architecture.html Comments and input welcome nikolaos.fistas@eurocontrol.int christophe.hamel@honeywell.com chuck.laberge@honeywell.com