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Provisional message formats for the DABS/NAS interface, revision 1

Published in:
MIT Lincoln Laboratory Report ATC-33,I

Summary

This document defines formats for messages which are to be transmitted between DABS and NAS facilities (en route or terminal). These messages include one-way Surveillance Reports to NAS and two-way Communications Messages. The latter support data link functions between NAS and DABS equipped aircraft, as well as aiding in the monitoring and control of DABS sensors. These message formats will be used in the design and construction of interface equipment and ground data links for prototype system test and evaluation at NAFEC during Phase II of the DABS Development Program; and, with modifications resulting from this test and evaluation effort, will form the basis for the operational implementation of DABS. This document supersedes FAA-RD-74-63, dated 25 April 1974.
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Summary

This document defines formats for messages which are to be transmitted between DABS and NAS facilities (en route or terminal). These messages include one-way Surveillance Reports to NAS and two-way Communications Messages. The latter support data link functions between NAS and DABS equipped aircraft, as well as aiding in the...

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Simulation of the DABS sensor for evaluating reply processor performance

Author:
Published in:
MIT Lincoln Laboratory Report ATC-28

Summary

This report describes the elements of a simulations program that was designed to perform a realistic evaluation of a variety of reply processing techniques, antenna design parameters and receiver characteristics for a DABS sensor. The reply processing techniques are limited to the generation of information bit and monopulse off-boresight azimuth estimates for DABS downlink messages. The report describes the detailed characteristics of two elements of the simulation program; the data generator and reply processor, and the high degree of versatility incorporated within these elements to allow for a great many performance tradeoff studies.
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Summary

This report describes the elements of a simulations program that was designed to perform a realistic evaluation of a variety of reply processing techniques, antenna design parameters and receiver characteristics for a DABS sensor. The reply processing techniques are limited to the generation of information bit and monopulse off-boresight azimuth...

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Provisional message formats and protocols for the DABS IPC/PWI display

Author:
Published in:
MIT Lincoln Laboratory Report ATC-35

Summary

This document specifies provisional formats for the data link portion of the ?signals-in-space? which are part of the DABS interrogations and replies. Also included is a discussion of the characteristics that these signals assume while transmitted from the transponder proper to the instrument which delivers the messages to the pilot. Specifically, formats, algorithms, and protocols are assigned to serve the IPC (lntermittent Positive Control), PWI (Proximity Warning Indicator), and ATC (numerical indicator) functions. The protocol and algorithm for the pilot acknowledgment link is also included in this paper.
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Summary

This document specifies provisional formats for the data link portion of the ?signals-in-space? which are part of the DABS interrogations and replies. Also included is a discussion of the characteristics that these signals assume while transmitted from the transponder proper to the instrument which delivers the messages to the pilot...

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Provisional message formats and protocols for the DABS 32-character alphanumeric display

Author:
Published in:
MIT Lincoln Laboratory Report ATC-36

Summary

Formats and protocols are described for tactical ATC displays to be driven by the Standard Message interface of a DABS transponder and capable of handling a succession of data transmissions, each of which is individually acknowledged via a transponder reply before the transmission of the succeeding segment. Specific codes are defined for a display device of up to 32 alphanumeric characters. Any displays defined or implied by this document are intended solely for use in the DABS test and evaluation program, and are not necessarily representive of recommended or require display devices for an operational DABS system.
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Summary

Formats and protocols are described for tactical ATC displays to be driven by the Standard Message interface of a DABS transponder and capable of handling a succession of data transmissions, each of which is individually acknowledged via a transponder reply before the transmission of the succeeding segment. Specific codes are...

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Provisional Signal Formats for the Discrete Address Beacon System, Revision I

Published in:
MIT Lincoln Laboratory Report ATC-30,REV.1

Summary

This document specified provisional DABS signal formats, i.e., the characteristics of the "signals-in-space" which form the DABS interrogations and replies. Also included is a discussion of the utilization of the described formats to effect the surveillance and data link communication functions for which DABS has been designed. These signal formats will be used in the design and construction of engineering development model transponders and interrogators for prototype system test and evaluation at NAFEC during Phase II of the DABS Development Program; and, with modifications resulting from this test and evaluation effort, will form the basis for the operational implementation of DABS.
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Summary

This document specified provisional DABS signal formats, i.e., the characteristics of the "signals-in-space" which form the DABS interrogations and replies. Also included is a discussion of the utilization of the described formats to effect the surveillance and data link communication functions for which DABS has been designed. These signal formats...

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Provisional data link interface standard for the DABS transponder

Published in:
MIT Lincoln Laboratory Report ATC-34

Summary

This document specifies provisional data link interface standards for the DABS transponder. It describes the function, timing, and electrical properties of the signals flowing to and from both the Standard Message Interface and the Extended Length Message Interface.
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Summary

This document specifies provisional data link interface standards for the DABS transponder. It describes the function, timing, and electrical properties of the signals flowing to and from both the Standard Message Interface and the Extended Length Message Interface.

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Provisional message formats for the DABS/NAS interface

Published in:
MIT Lincoln Laboratory Report ATC-33

Summary

This document defines formats for messages which are to be transmitted between DABS and NAS facilities (en route or terminal). These messages include one-way Surveillance Reports to NAS and two-way Communications Messages. The latter support data link functions between NAS and DABS equipped aircraft, as well as aiding in the monitoring and control of DABS sensors. These message formats will be used in the design and construction of interface equipment and ground data links for prototype system test and evaluation at NAFEC during Phase II of the DABS Development Program; and, with modifications resulting from this test and evaluation effort, will form the basis for the operational implementation of DABS.
READ LESS

Summary

This document defines formats for messages which are to be transmitted between DABS and NAS facilities (en route or terminal). These messages include one-way Surveillance Reports to NAS and two-way Communications Messages. The latter support data link functions between NAS and DABS equipped aircraft, as well as aiding in the...

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A summary of the DABS transponder design/cost studies

Published in:
MIT Lincoln Laboratory Report ATC-27

Summary

One of the major concerns in the DABS development program has been the cost of the DABS transponder. In order to realistically assess the impact on transponder cost of the many alternative techniques and design choices being considered for DABS, four study contracts were awarded to avionics manufacturers to design and estimate costs of special circuitry (in Phase I) and complete transponders (in Phase II). This report summarizes the major results of these design/cost studies, which cover general aviation, military, and air carrier transponder designs (including a retrofit kit for the military APX-72 transponder). The transponder design/cost studies have had a marked influence on the design of the DABS signal and message formats. Since the cost studies were basically intended for comparing link options for DADS, the transponder specifications used in these cost studies do not correspond in detail to current DABS transponder specifications. Therefore the cost data contained in this report cannot be taken to be completely representative of the cost of the finally specified DABS transponders.
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Summary

One of the major concerns in the DABS development program has been the cost of the DABS transponder. In order to realistically assess the impact on transponder cost of the many alternative techniques and design choices being considered for DABS, four study contracts were awarded to avionics manufacturers to design...

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Technical Assessment of Satellites for CONUS Air Traffic Control, Volume II - Random Access Aircraft-To-Satellite Techniques

Published in:
MIT Lincoln Laboratory Report ATC-26,II

Summary

A number of satellite system techniques have been suggested as candidates to provide ATC surveillance, communication, and/or navigation service over CONUS. All techniques perform postion determination by multilateration using a constellation of satellites. They can be categorized as follows: 1) Coordinated Aircraft-to-Satellite Techniques (CAST), 2) Random Access Aircraft-to-Satellite Techniques (RAST), and 3) Satellite-to-Aircraft Techniques (SAT). A technical assessment is made of the various techniques with no one particular technique emerging as superior; several feasible alternatives are identified. The assessment indicates that satellite bases techniques for CONUS ATC can be developed without relying on high risk technology. This volume deals with RAST, CAST and SAT are treated in companion volumes. A system employing RAST could operate by having each aircraft transmit a unique signature periodically, without any coordination of transmissions. The position of the aircraft is then obtained by multilateration using the arrival times of its signature at four or more satellites. Since aircraft transmissions are not coordinated, there is the possibility that different signatures may overlap at a satellite receiver. The resulting mutual interference is a factor in the performance of systems employing RAST. The critical technical aspects of RAST are explored with special emphasis on signaling formats, satellite coverage issues, degradation due to mutual interference and susceptibility to jamming.
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Summary

A number of satellite system techniques have been suggested as candidates to provide ATC surveillance, communication, and/or navigation service over CONUS. All techniques perform postion determination by multilateration using a constellation of satellites. They can be categorized as follows: 1) Coordinated Aircraft-to-Satellite Techniques (CAST), 2) Random Access Aircraft-to-Satellite Techniques (RAST)...

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Technical Assessment of Satellites for CONUS Air Traffic Control, Volume III - Satellite-To-Aircraft Techniques

Author:
Published in:
MIT Lincoln Laboratory Report ATC-26,III

Summary

A number of satellite system techniques have been suggested as candidates to provide ATC surveillance, communication, and/or navigation service over CONUS. All techniques perform postion determination by multilateration using a constellation of satellites. They can be categorized as follows: 1) Coordinated Aircraft-to-Satellite Techniques (CAST), 2) Random Access Aircraft-to-Satellite Techniques (RAST), and 3) Satellite-to-Aircraft Techniques (SAT). A technical assessment is made of the various techniques with no one particular technique emerging as superior; several feasible alternatives are identified. The assessment indicates that satellite bases techniques for CONUS ATC can be developed without relying on high risk technology. This three-volume report is a technical assessment of all three techniques. The present volume examines satellite-to-aircraft techniques (SAT). The remaining two volumes treat CAST and RAST. The assessment has shown that workable systems could be configured using any one of the three techniques without reliance on high risk technology. No one technique has emerged as superior. Rather several viable alternatives have been identified. All techniques appear to require more costly avionics than today's ground-based system.
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Summary

A number of satellite system techniques have been suggested as candidates to provide ATC surveillance, communication, and/or navigation service over CONUS. All techniques perform postion determination by multilateration using a constellation of satellites. They can be categorized as follows: 1) Coordinated Aircraft-to-Satellite Techniques (CAST), 2) Random Access Aircraft-to-Satellite Techniques (RAST)...

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