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Dual lane runway study, final report

May 22, 1973
  |
Project Report
Author:
Victor S. Dolat
…
Published in:
MIT Lincoln Laboratory Report ATC-17
Topic:
air traffic control
R&D area:
R&D group:

Summary

The issues in the dual lane runway problem were investigated via computer real time (man in the loop) and fast time (no human input during the simulation run) simulations in order to identify a dual lane runway configuration and determine operation strategies. The real time experiments were conducted using experienced ATC controllers and a pilot to observe the situation at interactive graphics CRT displays. Headsets and microphones were utilized to permit the normal controller/pilot interchanges. Flight strips as used in control tower cabs were employed to further simulate controller workload. Based on information gained during early real time controller experiments, a programmed controller concept (fast time) was adopted. A series of dual lane runway computer simulation experiments were performed to investigate the pertinent dual lane issues: centerline spacing, arrival/departure preference, parallel taxiway, threshold stagger, and hiqh speed exits. In addition, time was spent analyzing operational high density airport terminal facilities. Airport administrative and operations personnel were interviewed to obtain their views on high density operations and the dual lane concept. Peak rush hour periods were sought out to detenTIine control strategies employed indirecting peak period traffic. Air crews utilizing these high density airport terminals were interviewed in the course of their operations into and out of these major hub airports.
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Summary

The issues in the dual lane runway problem were investigated via computer real time (man in the loop) and fast time (no human input during the simulation run) simulations in order to identify a dual lane runway configuration and determine operation strategies. The real time experiments were conducted using experienced...

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Dual lane runway study, final report

Concepts for improvement of airport surveillance radars

February 26, 1973
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Project Report
Author:
Charles E. Muehe
…
Published in:
MIT Lincoln Laboratory Report ATC-14
Topic:
radar
R&D area:
R&D group:

Summary

This report reviews the performance of operational ASR's, discusses each type of clutter with which the target must compete, examines presently employed methods of overcoming clutter and several state-of-the-art techniques which have not found their way into the ASR's for one reason or another. It concludes by describing two radars, one at S-band and one at UHF, which are believed to come closest to fulfilling ASR requirements in advanced ARTS facilities. The major improvements in performance will be derived from the use of linear optimum signal processing. Further gains will be achieved through the use of adaptive thresholds. STC will combat bird clutter. The radar will incorporate proper shaping of the antenna pattern so that aircraft off the peak of the antenna elevation beam will not be at a disadvantage compared to moving clutter at the peak. The recommended radar concepts also include radial velocity determination by Doppler measurement. This should prove of value in maintaining target tracks and in discrimination against ground vehicles.
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Summary

This report reviews the performance of operational ASR's, discusses each type of clutter with which the target must compete, examines presently employed methods of overcoming clutter and several state-of-the-art techniques which have not found their way into the ASR's for one reason or another. It concludes by describing two radars...

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Concepts for improvement of airport surveillance radars

A high performance, low cost, air traffic control radar

February 15, 1973
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Technical Report
Author:
Charles E. Muehe
…
Published in:
MIT Lincoln Laboratory Report TN-1973-12
Topic:
air traffic control
R&D area:
R&D group:

Summary

Recent improvements in the technology of electronically switched antennas and digital signal processing make possible a relatively high performance, low cost, surveillance radar. The radar described employs an electronically step-scanned, cylindrical antenna together with an advanced digital signal processor to give superior MTI performance at an estimated cost of less than half the present S-band ASRs. The radar output consists of narrow band, digital target reports free of false alarms, suitable for transmission over telephone lines. Remote radar operation using digital, bright, scan-history displays becomes practical as does easy incorporation of beacon and direction finder outputs along with digitally generated video maps. The complete absence of moving parts, the low power transmitter and the largely solid-state construction will provide high reliability and low maintenance costs. These techniques are most easily and economically implemented in the UHF band, but a similar L-band radar can be designed with somewhat increased complexity and cost. The techniques and background studies employed in the design of the proposed radar evolved over a period of three or four years as a result of work for the Air Force under Contract F19628-73-C-0002. Some of these techniques are being applied to improve the MTI performance of the ASR under FAA Contract DOT-FA71WAI-242.
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Summary

Recent improvements in the technology of electronically switched antennas and digital signal processing make possible a relatively high performance, low cost, surveillance radar. The radar described employs an electronically step-scanned, cylindrical antenna together with an advanced digital signal processor to give superior MTI performance at an estimated cost of less...

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A high performance, low cost, air traffic control radar

A maximum-likelihood multiple-hypothesis testing algorithm, with an application to monopulse data editing

February 9, 1973
  |
Technical Report
Author:
Edward J. Kelly
Published in:
MIT Lincoln Laboratory Report TN-1973-7
Topic:
air traffic control
R&D area:
R&D group:

Summary

A simple algorithm for multiple-hypothesis testing, based on a generalization of likelihood ratio testing between pairs of hypotheses, is developed and applied to a specific problem. The problem arises in connection with an amplitude comparison monopulse system in an Air Traffic Control application. In particular, it is desired to measure target azimuth in a beacon system in the presence of interference and multipath. The multiple hypotheses relate to the presence or absence of a desired signal, with or without either of two kinds of interfering signal. The analysis leads to a new technique of data editing, or processing, to detect the presence of interference.
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Summary

A simple algorithm for multiple-hypothesis testing, based on a generalization of likelihood ratio testing between pairs of hypotheses, is developed and applied to a specific problem. The problem arises in connection with an amplitude comparison monopulse system in an Air Traffic Control application. In particular, it is desired to measure...

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A maximum-likelihood multiple-hypothesis testing algorithm, with an application to monopulse data editing

The influence of surveillance system parameters on automated conflict detection and resolution

November 29, 1972
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Project Report
Author:
John W. Andrews
…
Published in:
MIT Lincoln Laboratory Report ATC-15
Topic:
collision avoidance
R&D area:
R&D group:

Summary

The effects of sensor accuracy, data rate, and message delivery delay upon automated conflict detection,and resolution processing is analyzed and particular considerations for DABS/IPC operation are discussed. Various options in the design of the algorithmic logic are enumerated and a particular logic is chosen for quantitative inspection. Performance sensitivity calculations for the conflict detection and command generation functions are then presented. The influence of algorithmic logic and traffic environment upon surveillance requirements is delineated.
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Summary

The effects of sensor accuracy, data rate, and message delivery delay upon automated conflict detection,and resolution processing is analyzed and particular considerations for DABS/IPC operation are discussed. Various options in the design of the algorithmic logic are enumerated and a particular logic is chosen for quantitative inspection. Performance sensitivity calculations...

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The influence of surveillance system parameters on automated conflict detection and resolution

A theory for optimal MTI digital signal processing, supplement I

October 30, 1972
  |
Technical Report
Author:
Robert J. McAulay
Published in:
MIT Lincoln Laboratory Report TN-1972-14-SUP-I
Topic:
signal processing
R&D area:
R&D group:

Summary

In the report, "A Theory for Optimal MTI Digital Signal Processing. Part I. Receiver Synthesis," (1), the problem of eliminating scanning ground clutter from an aircraft surveillance radar was examined from a statistical decision theoretical point of view. An optimum processor was derived which could be approximated by a clutter filter followed by a discrete Fourier transform (DFT). In this report, additional numerical work is documented that compares the performance of the pulse cancellers, pulse cancellers with feedback and the DFT with that of the optimum processor. The issue of coherent vs incoherent integration gain is considered by comparing the filters only on their ability to reject clutter. A clutter rejection improvement factor is defined and used to compare the various filters. It is shown that the pulse cancellers can be quite effective in rejecting clutter provided the input clutter power is not too large and that additional gains are possible using the DFT.
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Summary

In the report, "A Theory for Optimal MTI Digital Signal Processing. Part I. Receiver Synthesis," (1), the problem of eliminating scanning ground clutter from an aircraft surveillance radar was examined from a statistical decision theoretical point of view. An optimum processor was derived which could be approximated by a clutter...

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A theory for optimal MTI digital signal processing, supplement I

An experimental UHF ground surveillance radar, volume II

October 12, 1972
  |
Technical Report
Author:
Lincoln Cartledge
…
Published in:
MIT Lincoln Laboratory Report TR-497-II
Topic:
radar
R&D area:
R&D group:

Summary

This is Volume 2 of the final report summarizing two years of work on ground-based foliage-penetration radar. The design and implementation of a breadboard radar system and of a theoretical and experimental investigation of target and propagation phenomena specific to the foliage-penetration problem are described. Volume 1 comprises three main sections: a short introduction; an overall description of the radar; and detailed descriptions of the hardware and software subsystems in the radar. Volume 2 describes the use of the radar as a measurements system for studying targets and the clutter environment, in addition to its use for demonstrating the feasibility of radar detection of walking men in foliage. Investigations of target return spectra, clutter return spectra, and clutter return amplitude statistics are reported. Theoretical models relating clutter spectra to wind turbulence and tree resonances are presented and compared with experimental results. Similarly, a previous theoretical prediction of target return spectra is compared with experimental results. Clutter return amplitude statistics are measured and found to be Gaussian under certain conditions. Finally, Vol.2 contains some comments on the relationships between the subclutter visibility and various parameters of digital MTI systems.
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Summary

This is Volume 2 of the final report summarizing two years of work on ground-based foliage-penetration radar. The design and implementation of a breadboard radar system and of a theoretical and experimental investigation of target and propagation phenomena specific to the foliage-penetration problem are described. Volume 1 comprises three main...

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An experimental UHF ground surveillance radar, volume II

A theory for optimal MTI digital signal processing, part II. signal design

October 4, 1972
  |
Technical Report
Author:
Robert J. McAulay
Published in:
MIT Lincoln Laboratory Report TN-1972-14-II
Topic:
air traffic control
R&D area:
R&D group:

Summary

In Part I of this report the optimum MTI receiver was derived and analyzed for the case in which the radar pulses were emitted from the transmitter equally spaced in time. For typical long range ATC surveillance radars , aliasing of the target and clutter spectra results in detection blind speeds at multiples of approximately 70 knots. It is well known operationally that these blind speeds can be eliminated by staggering the transmitter PRF. Heretofore, there has been no thorough theoretical analysis of the effect of staggered PRF on the spectral distribution of the target and clutter signals. It is shown in Part II that the clutter spectral density continues to fold over at the PRF, but that the signal spectrum becomes dispersed in frequency, somewhat like an anti-jam signal. The effect that this phenomenon has on the performance of the optimum processor is evaluated in terms of the signal-to-interference ratio (SIR) criterion that was derived in Part I. It is further noted that even when the target Doppler shifts are more than one PRF apart, the spectra are distinguishable, suggesting that unambiguous Doppler estimation may be possible. This concept is explored in detail using the MTI ambiguity function. It is shown that good SIR performance can be obtained by choosing the stagger parameters to minimize the height of the subsidiary Doppler side-lobes. The resulting design problem is noted to be similar to that of obtaining good antenna patterns for arrays having non-uniformly spaced elements.
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Summary

In Part I of this report the optimum MTI receiver was derived and analyzed for the case in which the radar pulses were emitted from the transmitter equally spaced in time. For typical long range ATC surveillance radars , aliasing of the target and clutter spectra results in detection blind...

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A theory for optimal MTI digital signal processing, part II. signal design

Dual lane runway study, interim report, Project 082-421-214

September 14, 1972
  |
Project Report
Author:
Victor S. Dolat
…
Published in:
Project Report ATC-11, MIT Lincoln Laboratory
Topic:
air traffic control
R&D area:
R&D group:

Summary

An overview of the issues involved in the design of dual lane runways is presented. These issues include: centerline spacing, parallel taxiway, high speed exits, midpoint versus end point crossing, threshold stagger, and departure/arrival runway preference. An interactive graphics simulation was developed on the TX-2 computer. The simulation provides the capability for an airport designer to easily input dual lane runway configurations. ATC controllers were employed for over 100 hours to control and direct simulated traffic to various dual lane configurations. A set of preliminary criteria for dual lane runway configurations are presented along with recommendations for future work.
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Summary

An overview of the issues involved in the design of dual lane runways is presented. These issues include: centerline spacing, parallel taxiway, high speed exits, midpoint versus end point crossing, threshold stagger, and departure/arrival runway preference. An interactive graphics simulation was developed on the TX-2 computer. The simulation provides the...

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Dual lane runway study, interim report, Project 082-421-214

Comparison of immunity to garbling for three candidate modulation schemes for DABS

August 14, 1972
  |
Project Report
Author:
David A. Shnidman
Published in:
MIT Lincoln Laboratory Report ATC-12
Topic:
surveillance
R&D area:
R&D group:

Summary

The performance of three candidate modulation schemes for DABS is analyzed in this report and a comparison on the basis of probability of error per bit is made. The three types of modulation are PAM, DPSK, and FSK. The results show that, at a given level of interference and signal-to-noise ratio, DPSK and FSK have a lower P(e)/bit than PAM and this difference is significant in most cases. In addition to P(e)/bit, however, the choice of modulation and message format depends on the capacity required, bandwidth occupancy, and cost of implementation. This list consideration is especially important with regard to the transponder.
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Summary

The performance of three candidate modulation schemes for DABS is analyzed in this report and a comparison on the basis of probability of error per bit is made. The three types of modulation are PAM, DPSK, and FSK. The results show that, at a given level of interference and signal-to-noise...

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Comparison of immunity to garbling for three candidate modulation schemes for DABS
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