The prospect of using phased array antennas in vehicle-borne antennas of Communications Satellite Corporation
Radio engineering. Electronics. Telecommunication systems
Аuthors, , *
Moscow Aviation Institute (National Research University), 4, Volokolamskoe shosse, Moscow, А-80, GSP-3, 125993, Russia
Recently Communications Satellite Corporation (COMSAT) has been rapidly developing . In this connection, there is a need to work out antenna systems with high power gain (about 35-60 dB), and coverage area, which is a cone of revolution with a vertex angle of 8,7º. Such antenna systems may be created either in the form of a multibeam antenna or a phased array antenna. It is well known that phased arrays have redundancy emitters compared with their theoretical minimum quantity , but this phenomenon is poorly studied.
This article presents the directional characteristics of phased array antennas with circular and square aperture within the different positions of the elements. Horn antennas with round and square aperture were used as emitters of phased arrays. As a result the dependence of the level and position of side lobe interference from a fixed number of emitters with the fixed dimension of phased array was greaped, as well as the dependence of redundance coefficient from the amount of redundancy and the emitter levels of the interference maxima for different efficiency coefficients. A comparative analysis of the dependence stated above was held for various identical in size antenna gain of phased array antennas.
The analysis determined the dependence of the interference sidelobes from radiators redundance coefficient. It helps to minimize the computing power required for the beam steering of phased array antennas, as well as to improve the constructive and technological parameters.
In the result the best formation structure of phased array antenna was chosen in terms of minimum quantity of emitters and the level of interference maximum that is not exceeding the level of side lobe. It has been established that the best phased array is considerably higher than the coefficient of highest redundancy identical multibeam antenna array described in [2 ] and the one, that consists of the multibeam «large aperture» emitters. Based on the results it is concluded that the use of phased arrays is not always justified and does not lead to the desired results, and therefore further detailed researches are required in development of phased array antennas or multibeam antenna arrays for vehicle-borne antennas of Communications Satellite Corporation.
Keywords:phased array, global satellite communications, aperture emitter, side lobe interference, coefficient redundancy, the minimum number of emitters, the directivity pattern
- Jones D.E. A Limited-scan, 20 GHz, active transmitting antenna for space applications, Digest of the IEEE APS International Symposium, Albuquerque, NM, 1982,vol. 2, pp. 435-438.
- Skobelev S.P. Fazirovannye antennye reshetki s sektornymi partsial’nymi diagrammami napravlennosti (Phased array antennas with sector partial pattern), Moscow, Fizmatlit, 2010, 320 p.
- Ponomarev L.I., Vechtomov V.A., Miloserdov A.S. Antenny, 2012, no. 5, pp. 52-65.