Experimental confirmation of

the Mushiake relationship,

Z = Z0/2≒188.4 [Ω],
where Z is the input impedance of the antenna,
and Z0 is the intrinsic impedance of the medium.

Fig. 1. Measured input impedances of the alternate-leaves type self-complementary antenna (or Square SCA ) plotted on the
Smith chart ( Z0S = 50 [Ω] ).

The broadband property of the input impedance is experimentally well proven for frequencies higher than the lowest frequency where the longest leaf of this antenna is quarter-wave frequency.

Detailed explanations are shown in a book authored by Yasuto Mushiake :
Self-Complementary Antennas ―Principle of Self-Complementarity for Constant Impedance―, 139 pages, Springer-Verlag London Ltd., London, pp. 81-88, 1996.

Fig. 2. Truncated alternate-leaves type self-complementary antenna (or Square SCA). The dimensions are shown in mm.
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