# Presentation: 317624

## Technical ADS-B/Situational Awareness Link Assessment Activities

- RTCA Free Flight Select Committee
- January 12, 2000 Status
- George Ligler, PMEI
- Co-Chair, Phase I LET
- Presentation by Dr. Stan Jones, MITRE / CAAASD

## Safe Flight 21 (SF21) Technical Link Assessment Task:  Phase I

- _Technical_ Evaluation of 1090 MHz Extended Squitter, VHF Digital Link (VDL) Mode 4, and Universal Access Transceiver (UAT) ability to support RTCA-defined Free Flight Operational Enhancements
- Services considered were ADS-B, TIS-B, and FIS-B.

- Technical ADS-B/Situational Awareness Link Assessment Activities

- January 12, 2000

## SF 21 Phase I Link Evaluation Team

- Responsible to the SF21 Steering Committee, a Subgroup of the RTCA Free Flight Select Committee
- Subject Matter Experts for each Candidate Link
- Team members from FAA, Mitre, Johns Hopkins
- Close Coordination with Eurocontrol ADS-B Program

- Technical ADS-B/Situational Awareness Link Assessment Activities

- January 12, 2000

## SF 21 Link Evaluation:  Phase I

- Developed Link Evaluation Criteria
- Characterized Candidate Links
- Agreed on Traffic Scenarios for Evaluation
- Gathered/Collected Flight Test Data
- Performed Initial Analyses and Simulations
- Took Top-Level Look at Spectrum Needs
- Agreed on 11 Initial Findings
- Reported on Above in November 1999

- Technical ADS-B/Situational Awareness Link Assessment Activities

- January 12, 2000

## Phase I Initial Findings

- Only Included if Phase I Technical Team was Unanimous
- 1090 Extended Squitter and VDL Mode 4:  Extensive Prior Work Recognized
- UAT:  Simplest Technical Concept
- Important Remaining Efforts to Field Any of the 3 Candidates

- Technical ADS-B/Situational Awareness Link Assessment Activities

- January 12, 2000

## Phase I Initial Findings (2 of 4)

- VDL Mode 4:  As Proposed, Does not meet all ADS-B MASPS State Vector Update Requirements in all Airspace Domains--Would Need More Channels
- 1090 MHz Extended Squitter:  Needs Improved Receivers to meet all ADS-B MASPS Range and Integrity Requirements

- Technical ADS-B/Situational Awareness Link Assessment Activities

- January 12, 2000

## Phase I Initial Findings (3 of 4)

- UAT:  Standards Development Yet to be Commenced and No Extensive Validation Experience
- Spectrum Status/Findings for all 3 Links
- Multipath:  VDL Mode 4 Best on Surface, Particularly in Gate Areas;  L-Band links, with more antennas than needed for VDL Mode 4, will support movement area

- Technical ADS-B/Situational Awareness Link Assessment Activities

- January 12, 2000

## Phase I Initial Findings (4 of 4)

- Spectrum
- 1090 MHz:  Approved air-to-air.  Carrier Frequency and Bandwidth Specifically Defined.  Further validation for Uplink Services/Surface Transmission Needed
- UAT:  U.S. Spectrum Allocation can be Accomplished within 6 months
- VDL Mode 4:  U.S. Allocation of Needed Frequencies Requires Time, But Can Be Done

- Technical ADS-B/Situational Awareness Link Assessment Activities

- January 12, 2000

## Technical Link Assessment:  Phase II Activities  

- FAA, with the Industry, Developing a Plan for Making a Formal ADS-B/Situational Awareness Link Decision in mid-2001
- Phase II Activities (Technical, Cost/Benefit, Institutional) To Support This Directly
- Technical Phase II Activities, Scheduled to be Completed in CY2000, will Build upon SF21 Link Evaluation Work-to-Date

- Technical ADS-B/Situational Awareness Link Assessment Activities

- January 12, 2000

## Phase II Technical Link Assessment Tasks

- Include Identified Operational Needs beyond those of SF21 (FAA/Eurocontrol)
- Consider Impact of Government/Industry Surveillance Operational Concept
- Factor in Impacts of ADS-B Operational Safety Assessment
- Complete Recommended Analyses and Simulations, Spectrum Considerations, etc.

- Technical ADS-B/Situational Awareness Link Assessment Activities

- January 12, 2000

## Phase II Technical Link Assessment 

- FAA Requesting Support Desired from RTCA for Phase II (Technical) Assessment
- Eurocontrol Will Officially Join the Team
- SF21 Steering Committee Phase I Success  with Technical Team to be Leveraged
- Membership of Technical Assessment Team Being Finalized--Limited Changes to Phase I LET

- Technical ADS-B/Situational Awareness Link Assessment Activities

- January 12, 2000

## Phase II Technical Link Assessment (continued)

- Recommended Simulation/Modeling Tasks are in Process
- Initial Phase II Technical Link Assessment Team Meeting Tentatively Scheduled for late February

- Technical ADS-B/Situational Awareness Link Assessment Activities

- January 12, 2000