Accession Number : ADA325313

Title :   Methods of Improving High Frequency Direct Injection Testing.

Descriptive Note : Final rept. 1 Jan 96-31 Jan 97,

Corporate Author : FIORE INDUSTRIES INC ALBUQUERQUE NM

Personal Author(s) : Lehr, Jane ; Sizemore, Roy ; Barre, Paul ; Johnson, Eric

PDF Url : ADA325313

Report Date : 31 JAN 1997

Pagination or Media Count : 120

Abstract : Direct injection testing is a valuable tool for identifying electromagnetic effects and critical subsystems prior to expensive, labor intensive free-field testing. However, as the frequencies of interest increase, the method becomes less reliable and the measurement techniques become more difficult. A major problem has been the frequency response of the voltage probes. This effort has identified the cause of the degradation of the voltage dividing ratio with frequency, through experiment and circuit simulation, as a capacitive effect. Moreover, the effective capacitance has been quantified, and constraints on the resistive element have been devised. An improved compact voltage probe is demonstrated which shows a flat frequency response to 3 GHz. Other issues which have been addressed are the importance of measuring the node impedance to ground; comparison of direct injection vulnerability levels with those obtained with free field testing; the practice of using incident power as a metric; using a transmission line as a voltage probe; and probe loading effects.

Descriptors :   *HIGH FREQUENCY, *VOLTAGE, *ELECTRICAL IMPEDANCE, TEST AND EVALUATION, ELECTROMAGNETIC PROPERTIES, VULNERABILITY, BROADBAND, FREQUENCY RESPONSE, CIRCUIT ANALYSIS, NARROWBAND, CAPACITANCE, ELECTRICAL LOADS, VOLTAGE DIVIDERS.

Subject Categories : Electricity and Magnetism
      Radiofrequency Wave Propagation

Distribution Statement : APPROVED FOR PUBLIC RELEASE