Publications
Provisional message formats for the DABS/NAS interface
Summary
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...
False target elimination at Albuquerque using ARTS-III software
Summary
Summary
Lincoln Laboratory has been assisting the U.S. Air Force Weapons Laboratory in the study of ATCRBS false targets caused by reflections from buildings at Albuquerque International Airport/Kirtland AFB. This paper discusses the false target situation there and proposes two algorithms for correcting it in ARTS-III software. The simpler of the...
Bistatic scatter from rain
Summary
Summary
An experimental investigation of bistatic scatter from rain was conducted using a 143 km scatter path at frequencies of 4.5 and 7.7 GHz. The ratio of transmitted to received power (transmission loss) was measured for scattering angles ranging from6\degto130\deg. Simultaneous weather radar observations were made at a frequency of 1.3...
The rain range experiment -- propagation through a simulated rain environment
Summary
Summary
The rain range experiment was conducted to test the adequacy of the assumptions usually made in the analysis of attenuation or phase shift due to rain: spherical drop shape, Mie scattering for a single drop, and single scattering theory for the coherent summation of the effects of each drop. A...
A summary of the DABS transponder design/cost studies
Summary
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...
Technical Assessment of Satellites for CONUS Air Traffic Control, Volume II - Random Access Aircraft-To-Satellite Techniques
Summary
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)...
Summary of results of antenna design cost studies
Summary
Summary
Design/cost studies on antenna systems for DABS have been carried out by Texas Instruments and Westinghouse under Lincoln Laboratory sponsorship. For independent, mechanically-rotating systems aperture widths between 10' and 35' and heights between 4' and 16' were considered, with estimated corresponding production costs ranging from $10K to more than $200K...
Technical Assessment of Satellites for CONUS Air Traffic Control, Volume III - Satellite-To-Aircraft Techniques
Summary
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)...
A system for acoustic-phonetic analysis of continuous speech
Summary
Summary
A system for acoustic-phonetic analysis of continuous speech is being developed to serve as part of an automatic speech understanding system. The acoustic system accepts the speech waveform as an input and produces as output a string of phoneme-like units referred to as acoustic phonetic elements (APEL'S). This paper should...
Report on DABS/ATCRBS Field Testing Program
Summary
Summary
The purpose of this field test program was to verify laboratory measurements of the effect of DABS uplink signal formats on ATCRBS transponders. The DABS interrogations tested were: (i) a combined ATCRBS Mode A/DABS All-Call consisting of a standard Mode A interragation with an additional pulse following the P(3) pulse...