Aerial Design in Inductive Loop Telemetry

Abstract

Two problems are considered which concern circular loop receiving aerials used in inductive loop telemetry. The first is that certain transmitter orientations give rise to signal nulls. The second is the optimum aerial size. By inverting the roles of the transmitting and receiving aerials, a simple way of describing the orientations which give rise to signal nulls is found. The factors which limit the range of an aerial are discussed and a simple method for deciding whether or not it is advantageous to enlarge or reduce the aerial radius is given.