Variations in mutual coupling correction factors for resonantdipoles used in site attenuation measurements

摘要

Site attenuation measurements using resonant dipole antennas arecommonly used to certify test sites for compliance testing to theFederal Communication Commission Part 15 requirements. Mutual couplinghas previously been shown to affect the impedance of resonant dipoleantennas. It is pointed out that a correction factor must be added toANS C63.4 normalized site attenuation for these measurements to agreewith theoretically calculated results below 200 MHz. An accuratemethod-of-moments technique of predicting horizontal and vertical siteattenuation at three meters with resonant antennas is presented. Theelectrical properties of the antenna balun can be input directly intothe model, the exact antenna wire structure including the segmentedelements can be included, and all mutual coupling effects are modeled inthe problem solution