Publications

The angular resolution and tracking of closely spaced targets is a classical radar problem which is receiving increased attention, and terrain multipath (e.g., reflections) has long been recognized to be a principal limitation on the achievable accuracy of radar elevation trackers at low elevation angles. A variety of techniques have...

This paper presents the results of an experimental program to obtain a better quantitative understanding of low angle microwave propagation phenomena needed to assess the potential for improved elevation tracking performance. It has long been recognized that terrain multipath (e.g., reflections and/or shadowing) are a principal limitation on the achievable...

This report describes the MIT Lincoln Laboratory Transportable Measurements Facility (TMF), a special purpose beacon interrogator patterned after the Discrete Address Beacon Sensor. This van-mounted experimental beacon system includes all ATCRBS/DABS reply processing and monopulse processing, but not other DABS processing. It was developed to collect data at various locations...

This report examines the technical feasibility of alternate waveforms to perform the GPS functions and to result in less complex receivers than is possible with the GPS C/A waveform. The approach taken to accomplish this objective is (a) to identify, after a quick broad overview, a few promising waveforms, (b)...

This document provides a functional description of the Discrete Address Beacon System (DABS), a combined secondary surveillance radar (beacon) and ground-air-ground data link system capable of providing the aircraft surveillance and communications necessary to support ATC automation in future traffic environments. DABS is capable of common-channel interoperation with the current...

This paper describes the technique of designing the network management coverage map files necessary to coordinate a network of DABS sensors. First, the concept of the DABS network is defined, and the functions of Network Management are briefly described, as they relate to the coverage map. Then, the rationale for...

In current ATC radars, high altitude targets are at a disadvantage when competing with low altitude undesired returns such as ground clutter and birds. The "zoom antenna" technique is proposed as a means of virtually eliminating this problem. An implementation based on control of multiple elevation beams during each range...

This report presents work done during phase 3 of the US national Microwave Landing System (MLS) program toward developing a computer simulation model of the MLS multipath effects, the experimental validation ot the model, and the application of the model to investigate multipath performance of ICAO proposals for the new...

This paper provides information on site-associated phenomena that affect the proper operation of a DABS sensor and therefore warrant serious consideration when siting a radar. The DABS-related discussion is intended to be a supplement to the ATCRBS siting criteria presented in the FAA Primary/Secondary Terminal Radar Siting Handbook. The paper...

The MTD (Moving Target Detector) is an automated radar signal and data processing system designed to improve the performance of air surveillance radars in various forms of clutter while providing a low output false alarm rate. This paper briefly describes the architecture of the MTD processor and presents the results...