Aerospace Medicine Technical Reports
FAA Office of Aerospace Medicine
Civil Aerospace Medical Institute
Report No: DOT/FAA/AM-05/19
Title and Subtitle: Terminal Radar Approach Control: Measures of Voice Communications System Performance
Report Date: October 2005
Authors: Prinzo OV, McClellan M
Abstract: Effective communications in the National Airspace System (NAS) is an essential safety component of successful air travel. As the NAS migrates from its current ground infrastructure and voice communications system to one that encompasses both ground and airborne systems, digital data transmission may become the principal communication medium.
As technological advances lead to innovations in communications system development, these emerging systems will be evaluated against the existing legacy system�s performance parameters such as setup delay, voice streaming, pause duration, and message propagation. The data presented here are but a first step in providing objective and quantifiable communications system performance metrics that may prove valuable to communication systems developers and personnel charged with evaluating, certifying, and deploying the next generation of communications systems.
The authors analyzed nearly 8,000 transmissions that represented the busiest air-ground communications from the five terminal radar approach control facilities with the highest number of operations in the contiguous United States. Typically, setup delays lasted 81 ms, voice streaming 2568 ms, pause duration 127 ms, and message propagation 73 ms for a total of 2849 ms per transmission. On average, transmissions were separated by 1736 ms of silence. Disruptions to efficient information transfer can result from blocked, stepped-on, and clipped transmissions � but they are rare events and occurred in only 1.16% of the sampled transmissions. A comparison between aircraft with and without disruptions revealed that when a disruption was present, an average of 14.54 messages were transmitted, compared with an average of 9.90 messages when no disruption was present. Even so, there appears to be some type of a detection mechanism in place to alert the controller to the presence of blocked transmissions.
The source is of this detection system is unclear; however, systems developers may want to exploit and expand this capability to include stepped-on and clipped transmissions.
Key Words: Communications, ATC Communication, Air Traffic Control
No. of Pages: 23
Civil Aerospace Medical Institute
Report No: DOT/FAA/AM-05/19
Title and Subtitle: Terminal Radar Approach Control: Measures of Voice Communications System Performance
Report Date: October 2005
Authors: Prinzo OV, McClellan M
Abstract: Effective communications in the National Airspace System (NAS) is an essential safety component of successful air travel. As the NAS migrates from its current ground infrastructure and voice communications system to one that encompasses both ground and airborne systems, digital data transmission may become the principal communication medium.
As technological advances lead to innovations in communications system development, these emerging systems will be evaluated against the existing legacy system�s performance parameters such as setup delay, voice streaming, pause duration, and message propagation. The data presented here are but a first step in providing objective and quantifiable communications system performance metrics that may prove valuable to communication systems developers and personnel charged with evaluating, certifying, and deploying the next generation of communications systems.
The authors analyzed nearly 8,000 transmissions that represented the busiest air-ground communications from the five terminal radar approach control facilities with the highest number of operations in the contiguous United States. Typically, setup delays lasted 81 ms, voice streaming 2568 ms, pause duration 127 ms, and message propagation 73 ms for a total of 2849 ms per transmission. On average, transmissions were separated by 1736 ms of silence. Disruptions to efficient information transfer can result from blocked, stepped-on, and clipped transmissions � but they are rare events and occurred in only 1.16% of the sampled transmissions. A comparison between aircraft with and without disruptions revealed that when a disruption was present, an average of 14.54 messages were transmitted, compared with an average of 9.90 messages when no disruption was present. Even so, there appears to be some type of a detection mechanism in place to alert the controller to the presence of blocked transmissions.
The source is of this detection system is unclear; however, systems developers may want to exploit and expand this capability to include stepped-on and clipped transmissions.
Key Words: Communications, ATC Communication, Air Traffic Control
No. of Pages: 23
Last updated: Friday, June 1, 2012