The circular loop antenna multiloaded with positive and negative resistors

Studies are made of both the driving-point impedance and the amplitude and phase distributions of the current in a circular loop which is driven by an arbitrary number of delta-function generators and loaded with an arbitrary number of lumped impedances. The only restriction imposed in the present treatment is that the elements (either generator or load) are spaced at equal intervals of
2\pib/m
along the circumference where
m
is the total number of elements and
b
is the radius of the loop. The numerical calculations include loads with negative resistances in order to take account of loops loaded with an element like an Esaki tunnel diode, with proper precautions against both self-oscillation and switching effects. A study of such precautions is to be considered separately. The experimental results agree quite well with theory except for the larger values of
\beta b
. The radiation patterns of the loop antennas with
\beta b=1
loaded with various resistors were also measured.