... system.¹

Under the SDI program of a decade ago it was widely understood that decoys could play an important role. The American Physical Society study of SDI of April 1987 did not present any detailed study of decoys, partly because such countermeasures were considered to be highly classified. Yet it did mention that very light decoys were practicable.

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... missile.²

We use the word missile to describe either the missile carrying the warhead or the warhead deployed by the missile.

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... students³

Michael Kasdan and Joshua Raha. These students' feasibility measurements, carried out at the University of Pennsylvania, appear in their theses.

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... engineers⁴

Abraham Friedman and Philip Farnum

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... chamber⁵

We wish to thank Prof. Nabil Farhat for use of his anechoic chamber facility for our studies.

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... antennas⁶

The spiral antennas were donated by AEL Defense Corporation of Lansdale, PA.

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... analyzers⁷

We wish to thank Lockheed Martin for loan of their Hewlett-Packard 8620 spectrum analyzer which was crucial for our measurements.

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... workers.⁸

Donald Carlson of the Moore School of Engineering was of great help in providing equipment useful in our laboratory measurements.

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... decoy.⁹

This approach has been known as ``antisimulation'', a concept that was treated earlier by R. L. Garwin.

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... GHz.¹⁰

M. B. Amin and J. R. James, The Radio and Electronic Engineer, 51 208 (1981)

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... AEL¹¹

We wish to thank Dr. George Sun of AEL Defense Corp. for arranging for the donation of the the spiral antennas used in our study.

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... literature.¹²

corner obstacles are discussed in the Antenna Engineering Handbook, Richard C. Johnson and Henry Jasik, McGraw-Hill, 1984 p. 40-19

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... decoys.¹³

S. Frankel, ``Endoatmospheric Decoys'', I/P Report 9610

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... ago,¹⁴

Reviews of Modern Physics 59 3 , July 1987

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... well.¹⁵

R. L. Garwin, ...

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... frame.''¹⁶

AIAA-Collection of papers ISBN-1-56357-187-6

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