One of the more comprehensive studies of consumer and industrial electronic equipment in high level microwave fields is the result of a series of measurements by the Engineering Experiment Station of the Georgia Institute of Technology in Atlanta, Georgia (individual references are supplied later in the report). This series of tests provides a valuable insight into what might be expected with SPS even though the tests were conducted at frequencies other than 2.45 GHz, and in a pulsed interference environment. The following material will summarize some of these results. The tests at Georgia Institute of Technology were designed to investigate the electromagnetic compatibility of the SAFEGUARD Ballistic Missile Defense System and consumer/industrial electronic equipments and systems operating within the site environment. Interference thresholds of a variety of devices were measured at interfering frequencies of 420 to 450 MHz and 3.1 to 3.5 GHz. Although it is primarily the 3.1 to 3.5 GHz tests that are of interest in this report, the lower frequency tests will also occasionally be discussed to give the reader a feeling for the effects of frequency. The test results described in the remainder of this section of the report were measured with an interference pulse width of 120 psec and a repetition rate of 400 pps. Although it is difficult to project results from a pulsed interference environment to the continuous case, the interference thresholds for continuous interference are not expected to be vastly different in view of the active interference mechanisms. Threshold values quoted in the following are all peak signal levels and denote the signal level where adverse reaction was first observed. It is important, throughout the following discussion, to realize that two distinctive interference mechanisms were observed during the tests. The first mechanism is called high-power interference, since it typically occurs at inter- ference levels above 10 mw/cm and is due to leakage of signals into the device being interfered with. High-power interference is usually frequency insensitive in that a change in frequency of the order of 100 MHz in either the interferer or victim does not produce any significant difference in interference characteristics. This phenomena is due, at least in part, to the fact that the amount of power coupled through apertures, cables, and wires is not significantly different over a frequency range such as the one from 3.1 to 3.5 GHz. In contrast, the second mechanism, which is designated low-power interference, typically occurs at interference levels below 10 mw/cm and is due to spurious or harmonic interactions between interferer and victim. A typical example of this
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