High speed radiation characteristics measurement equipment over the solid angle of a sphere to evaluate antennas attached to an 800 MHz cellular telephone

摘要

An improved measurement equipment for the radiation characteristics of a small antenna over the solid angle of a sphere has been developed on the basis of experimental investigations. It has been found from the measured results of directivity for a half-wavelength dipole antenna that a frequency coverage of 900 MHz can be obtained judging from the H-plane ripple of 2 dB. This measurement equipment displays the radiation characteristics over a sphere surrounding the test antenna for a short period of one minute including the measuring time. This equipment has been designed to evaluate an antenna attached to an 800-MHz hand-held cellular telephone.