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J a p a n 1 0 2 ) 1. r n R O W C T I O N invented in U.S.A. and Vierergruppe antemen invented i n Germany are most widely used for VHF TV broadcasting i n t h e world."The antenna which has become t h e most popular for VHF television broadcasting purposes is the superturnstile or batving antenna. !This antenna came i n t o use vith the opening of the commercial television broadcasting field in 1948.A t the Present time. over 75 percent of the antennas used for VHF transmitting purposes are superturnstiles."The super turnstile antenna is used i n Japan as w e l l as in U.S.A. Thisin Fig.1 shows t h e appearance of the original one when it vas first made public.antenna W a s invented by one of the writers, namely, Dr. Masters. The photoThe secret of t h i s antenna lies i n i t s complex shape. It is called a batwing antenna i n U.S.A. and "eine Schmetterlingsantene" in Germany i n view of its shape.bandwidth of one channel, but also over several adjoining channels. For example, the antenna for the Japanese high channels covers channels 4-12, i.e., the frequency range from 170-222 MHz, with VSMR less than 1.10. Various attempts have been made without much success t o explain why this antenna element exhibits such excellent vide-band characteristics. That i s , some said it w a s a kind of a slot antenna, or a s o r t of a brnach or plate antenna, or an antenna excited by a traveling wave. Every description(3)was only quantitative and mere guess work, thereby Endo(4 tried using simultaneous equations of one degree with 22 unknoms, l a c k i n exactness. D r . Sat0 and Mr. Kawakami, two of t h e writers, and Dr. be sinusoidal. assuming that currents flowing i n each conductor composing this antenna to of t h e s t r u c t u r e i n the horizontal end vertical plane. They also Calculated a i d o f t h e s o l u t i o n s for t h e above equations, and then the radiation patterns t h e power gain a d input impedance of t h i s antenna with t h e a i d of t h e spherical integral of these radiation characteristics.The r e s u l t w a s , however, not very satisfactory from the standpoint of rigor. THEORETICAL C-ON AHD CHARACTERISTICS OF BATWING AWIENNAA t the present time, super turnstile antennas(l), super gain antennas 1961, Ports and Rohrer(2)wrote as follows, This antenna has excellent characteristics not o n 4 over t h e 6 KIIZ hequency ' 7 They calculated current distributions along the antenna conductors with the Next,, ve rigorously calculated the characteristics of t h e batwing antenna using the M o m e n t Method proposed by Dr. Ifarrington(5), and conducted some physical experimenGs. A -del antenna was used whose s i z e w a s about two f i f t h s t h a t of a full s c a l e batwing antenna f o r t h e Japanese h i & channels, i -e . 3 with i t a designed center frequency 500 MHz. This antenna was intended t o be operate best over the frequency range of 425 t o 555 M I , 01 about two and half timca 170 t o 222 Nz. exploring the frequency range horn 300 t o 700 on Purpose t o C l m i f g its characteristics...