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Radiation Patterns of Unintentional Antennas: Estimates, Simulations, and Measurements



Perry F. Wilson


Electronic devices designed for purposes other than transmitting and receiving electromagnetic fields nonetheless act as unintentional antennas. Measurements methods are needed to characterize these antennas for electromagnetic compatibility tests; however, the rigor of precision antenna measurements is typically too costly and time consuming for electromagnetic compatibility applications. Alternate approaches are needed. This paper presents analytical estimates for the directivity of unintentional antennas based on the assumption that unintentional antennas will only randomly excite the available propagating spherical modes at a given frequency. This directivity estimate is then compared to simulated and measured data. Good agreement is shown. Directivity estimates combined with simple total radiated power measurements represent a useful alternative to direct antenna measurements for electromagnetic compatibility tests.
Proceedings Title
Antenna Measurements Techniques Association
Conference Dates
October 31-November 4, 2005
Conference Location
Newport, RI


antenna measurements, directivity, electromagnetic compatibility, unintentional antennas


Wilson, P. (2005), Radiation Patterns of Unintentional Antennas: Estimates, Simulations, and Measurements, Antenna Measurements Techniques Association, Newport, RI (Accessed May 25, 2024)


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Created November 1, 2005, Updated February 19, 2017