D. I. Voskpesenskiy - Ph.D. (Eng.), Professor, Head of Department of Radiophysics, Antennas and Microwave Technique of Moscow Aviation Institute. E-mail: voskr@mai.ru
E. V. Ovchinnikova - C.Sc. (Eng.), Associate Professor of Moscow Aviation Institute, Department of Radiophysics, Antennas and Microwave Technique. E-mail: oea8888@gmail.com
Bui Cao Ninh - Postgraduate Student of Moscow Aviation Institute, Department of Radiophysics, Antennas and Microwave Technique. E-mail: buicaoninh@gmail.com

In present time, cellular communication systems of the fourth generation are spreaded wide. They provide wideband unified radio access which allows video and multimedia content transmission. Selection of cellular communication standard explicitly determines the choice of telephone model class. The promising way in creating antennas of cellular telephones is designing compact antennas, operating in multiple combinations of frequency bands. In wideband operation, cellular telephones can be used in different countries where different standards are applied. The antenna is one of those parts which influences on cell phone design. Antenna's directional characteristics have effect on the quality of communication. Therefore, the rise of functionality of cellular telephones and expansion of 4G coverage on the market produce new requirements to the antenna. In the early times of cellular telephony, the miniature spiral antennas were spreaded wide. They were combined with a monopole antenna. However, external antennas are not so convenient comparing to microstrip flush-antennas. Therefore, modern telephones' designers use only the printed technology in antennas manufacturing. Microstrip patch antenna is a metallic conductor of some shape that is located on the grounded substrate. It can be successfully combined with the printed circuit board on which the microwave stages of handset are located. One of specific problem is designing wideband antenna which has to be embedded into the cellular telephone case. Sure, reasonable efficiency (antenna gain) has to be provided. Strict requirements are formulated to the directivity of cellular telephone's antenna. Reliable reception has to be ensured from any angle in urban areas. In addition, it is necessary to ensure the allowable value of power that is absorbed in person-s head and hand, in order to guarantee sanitary norms of irradiation of microwave frequency power. The article substantiates the need of designing small wideband antennas of cellular telephones. The different variants of these antennas and their directional characteristics are shown.