11: Common Antennas and Applications
- Page ID
- 24876
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- 11.2: Wire Antennas
- Exact solution of Maxwell’s equations for antennas is difficult because antennas typically have complex shapes for which it is difficult to match boundary conditions. Fortunately, most common wire antennas permit their current distributions to be guessed accurately relative to the given terminal current. Once the current distribution is known everywhere, the radiated fields, radiation and dissipative resistance, antenna gain, and antenna effective area can be calculated.
Thumbnail: Polar plots of the horizontal cross sections of a (virtual) Yagi-Uda-antenna. Outline connects points with 3 dB field power compared to an ISO emitter. (CC BY-SA 4.0 International; Timothy Truckle via Wikipedia)