A.A. Purinzova – Design Engineer of the 2nd category, JSC «SRI «Ekran» (Samara)
E-mail: firstname.lastname@example.org, email@example.com
Modern antenna requirements bandwidth supports maximum and minimum dimensions. Developed ultra-wideband (up to 1:20) spiral antenna with good radio characteristics in the required frequency range.
The radiation pattern of the spiral consists of two lobes. Unidirectional radiation can be obtained by placing the spiral in the body-cavity, while dramatically reducing the overlap in frequency (up to 1:2, 1:3). To suppress the back radiation and increase the bandwidth of a spiral antenna it is necessary to apply radar absorbing materials.
The article discusses the various options for optimizing spiral antenna overall dimensions, weight and achieving the maximum possible electrical characteristics. The minimum weight is achieved through the use of super-light radar-absorbent fillers. Radar-absorbent materials also reduce the height of the resonator housing.To reduce the geometric dimensions of antenna aperture and increased bandwidth, the branches of the spiral are made with sinusoidal curvature. The main problem was the development of a matching transformer, and output antenna connector was placed not in the bottom of the antenna housing and side. By optimising the conductive strip of the transformer and the printed circuit board pattern of the spiral in the program CST MICROWAVE STUDIO was able to achieve an acceptable VSWR in the desired frequency range.
Was designed and manufactured prototype of a spiral antenna. Measured VSWR of the antenna in the 2−18 GHz range less than 1.8, in the range 1−2 GHz is less than 3. The radiation pattern of the antenna in the entire frequency range of approximately 60*60°. The transformer spiral antenna smoothly changes the resistance from 50 Ohms to 187 Ohms.
Strictly speaking, the spiral antenna has a phase center, but within the main lobe of the wave radiated by a spiral antenna is nearly spherical. In CST MICROWAVE STUDIO have been calculated coordinates of the phase center relative to the center feeding spiral.
- Kaiser J.A. Antenna v vide dvuxzaxodnoj arximedovoj spirali // V kn. «Sverxshirokopolosny’e antenny’». M.: Mir. 1964. S. 151.
- Jones J.P., Taylor D.E., Morrow C.W. Spiral’naya malogabaritnaya antenna, rabotayushhaya pri bol’shoj moshhnosti // V kn. «Sverxshirokopolosny’e antenny’». M.: Mir. 1964. S. 193.
- Zhuk M.S., Molochkov Yu.B. Proektirovanie linzovy’x, skaniruyushhix, shirokodiapazonny’x antenn i fiderny’x ustrojstv. M.: E’nergiya. 1973.
- Yurczev O.A., Runov A.V., Kazarin A.N. Spiral’ny’e antenny’. M.: Sov. radio. 1974.
- Kurushin A.A., Plastikov A.N. Proektirovanie SVCh ustrojstv v srede CST MICROWAVE STUDIO. M.: «Izd-vo ME’I». 2010.
- E’lektronny’j resurs http://www.cst.com.
- Pat. RF № 2422954. Sverxshirokopolosnaya spiral’naya antenna / Korobejnikov G.V., Ivanova L.N., Koxnyuk D.D., Kudrin O.I., Zajczeva N.V.