Masters Theses

Abstract

"A radar guided missile seeker approaching a target arrives at a crossover point beyond which the entire target is illuminated by the missile seeker's radar antenna beam. When this occurs, for a complex target, the radar senses a time changing target center location which may greatly complicate the terminal tracking portion of the seeker's flight. This thesis documents various glint models in use today and compares the performance of these models by using a seeker model to determine the effect of glint on terminal tracking performance. A large volume of data has been compiled describing various radar characteristics of complex targets. Some of the glint models discussed herein are the result of independent investigations and some models are derived analytically. The return energy transmitted from a radar and reflected from a complex target is generally statistical in nature due to the random nature of the reflecting surfaces dispersed over the target vehicle and also because the target is continually changing aspect. A radar target's reflecting characteristics are of concern when a seeker is attempting to acquire the target and again when the seeker is closing on the target. A large amount of data exists for determining long range acquisition capabilities of various radar schemes. The acquisition of a target in a sea clutter background has been thoroughly investigated in the past decade and today's improved techniques (Moving Target Indication and Pulse Compression) have enabled moderately powered radars to acquire very small targets in high sea states. At long ranges, the individual target elements present a unified amplitude response (or appear as a point source). The main problem during acquisition is to reduce the viewing area to dimensions comparable to the target so that the target return will be distinguishable. This argument does not apply to an interferometer as target phase variations will still contribute to acquisition error, however the sophistication required to implement interferometers into a seeker design precludes their use for present day tracking schemes. Although acquisition problems can severely limit the response time of a seeker bearing vehicle or aircraft to an eminent attack threat, the inability of a radar seeker to operate in the presence of angle glint can render the seeker useless. A seeker's design must often be a compromise between tracking accuracy, acquisition capability, and dynamic versatility, since the weight and cost penalties associated with multiple radar tracking modes within a single seeker are prohibitive. Therefore, since the literature abounds with acquisition theory and techniques, the main portion of this thesis consists of analyzing the post-acquisition seeker performance in the presence of angular glint or angle noise. The glint models used in this analysis represent models in use at the present time. In addition, models which were derived are compared to determine the degree of correlation which exists between measured target models and those models which are derived from their statistical characteristics. The method employed for the evaluation is general in nature so that the procedure could be used to evaluate any subsequent glint model derivations. In addition, some recent work is summarized which demonstrates the advantages of using swept frequency techniques to improve radar tracking performance in the presence of angular glint"--Abstract, pages ii-iv.

Advisor(s)

Noack, Thomas L.

Committee Member(s)

Marshall, S. V., 1927-1999
Grimm, L. J.

Department(s)

Electrical and Computer Engineering

Degree Name

M.S. in Electrical Engineering

Publisher

University of Missouri--Rolla

Publication Date

1970

Pagination

x, 69 pages

Rights

© 1970 Franklin Delano Hockett, All rights reserved.

Document Type

Thesis - Open Access

File Type

text

Language

English

Subject Headings

Guided missiles -- Guidance systems -- DesignGuided missiles -- Control systems -- EvaluationRadar -- Antennas

Thesis Number

T 2648

Print OCLC #

6039106

Electronic OCLC #

882093732

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