Broadband Antenna with Practically Omnidirectional Radiation Pattern.

Fig. 1.Measured field patterns of Truncated alternate-leaves type self-complementary antenna or (Square SCA): (a) yz-plane,(b) xz-plane. (Electric field is in y-direction).

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

The alternate-leaves type self-complementary antenna (or Square SCA) has practically omnidirectional radiation pattern. 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.
Original paper:
T. Furuya, T. Ishizone, and Y. Mushiake: “Alternate-leaves type self-complementary antenna and its application to high gain broad-band antennas”,
IECE Technical Report, AP-77, No. 43, pp. 35-40,  (in Japanese), July 1977.
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