A necessary condition for the aforementioned reciprocity property is that the materials in the antenna and transmission medium are linear and reciprocal. Reciprocal (or bilateral) means that the material has the same response to an electric current or magnetic field in one direction, as it has to the field or current in the opposite direction. Most materials used in antennas meet these conditions, but some microwave antennas use high-tech components such as isolators and circulators, made of nonreciprocal materials such as ferrite. These can be used to give the antenna a different behavior on receiving than it has on transmitting, which can be useful in applications like radar. COUNT 4
QSN1 What must be true of the antenna and transmission medium for the repiprocity rule to apply ? ANS1 linear and reciprocal QSN2 What is one material that does not have this quality? ANS2 ferrite QSN3 How can the lack of this quality be used in an everyday way? ANS3 radar QSN4 What is called when the direction of the elctrical current does not make a difference to the current? ANS4 Reciprocal