Multiple-Arm Folded Monopole Antenna Operating Extremely Close to a Conductive Plane

The paper presents study of radiation properties of low profile folded multiple-arm dipole and design of monopole antennas operating extremely closely spaced above a conductive plane (as far as to 0.003 lambda₀) intended to use for radiofrequency identification of moving sportsmen in mass race in frequency band at 869 MHz. It is shown that complex conjugate matched monopole prototype can have satisfactory radiation efficiency in spite of the extremely low relative antenna height above the conductive plane used as a shielding of human body or metallic objects.