Accession Number : AD0438963


Title :   RE-ENTRY PROPAGATION AND ANTENNA STUDIES.


Descriptive Note : Final rept.,


Corporate Author : ELECTROMAGNETIC RESEARCH CORP COLLEGE PARK MD


Personal Author(s) : Wolff,Edward A


Report Date : 31 Mar 1961


Pagination or Media Count : 70


Abstract : The simulation measurements performed did not verify the type of relation derived theoretically for an insulated slotted sphere antenna. Study of the data suggests this is due to trapped waves with the dielectric medium. The measurements show the plasma seriously detunes the type of TM antenna used, even for small changes in refractive index and thicknesses which are very small electrically. An improved experimental procedure is suggested which would conform more closely to the situation postulated in the theoretical analysis, and serve as a better test of the theory. An automatic impedance matcher was designed to tune electronically a re-entry telemetry slot antenna to compensate for the detuning caused by the formation of the plasma sheath. The practicality of this matcher depends upon the availability of a ferroelectric material having low losses. An expected resonance necessary for effective performance of this material did not occur in the TM brand. This low Q precludes the use of this material in the matcher. (Author)


Descriptors :   *ANTENNA SIMULATORS , SIMULATION , PROPAGATION , SPHERES , EXPERIMENTAL DATA


Distribution Statement : APPROVED FOR PUBLIC RELEASE