Television Receiving Antenna System Component Measurements,

摘要

Relative gain of fifteen television receiving antennas was measured as a function of frequency and azimuth angle. Input voltage standing-wave ratio was measured as a function of frequency to determine the scalar impedance properties of the antennas. These antennas, a sample of those available from sources likely to be utilized by TV antenna installation technicians as well as consumers,ranged in price from $1.00to $78.00and in length from 18cm to 400cm. Insertion loss of a sample of system components,balanced-to-unbalanced line transformers and VHF/UHF signal splitters,was measured,and transmission line attenuation was obtained from manufacturers'data. Antenna gain,component insertion loss,transmission line attenuation,and calculated dipole antenna constant are the significant components of a power budget equation relating power flow in the TV signal field incident upon the antenna to the signal power available at the receiver. Results for four simple types of home installations are given. The range of the power budget data for best and worst combinations of antennas,transmission lines,and other system components illustrates the range of the power available at the receiver versus frequency for a specified power flow in the signal field.