This paper proposes a 8 × 1 sprout-shaped antenna array with low sidelobe level (SLL) for outdoor point to point applications. The array has the dimensions of 165 mm × 195 mm × mm and is designed on Rogers RT/Duroid 5870tm with the thickness of mm and permittivity of . In order to achieve low SLL, Chebyshev distribution weights corresponding to SLL preset at -30 dB has been applied to design the feed of the array. | VNU Journal of Science: Comp. Science & Com. Eng., Vol. 33, No. 1 (2017) 22-27 A 8×1 Sprout-Shaped Antenna Array with Low Sidelobe Level of -25 dB Tang The Toan1, Nguyen Minh Tran2, Truong Vu Bang Giang2,* 1 University of Hai Duong VNU University of Engineering and Technology, Hanoi, Vietnam 2 Abstract This paper proposes a 8 × 1 sprout-shaped antenna array with low sidelobe level (SLL) for outdoor point to point applications. The array has the dimensions of 165 mm × 195 mm × mm and is designed on Rogers RT/Duroid 5870tm with the thickness of mm and permittivity of . In order to achieve low SLL, Chebyshev distribution weights corresponding to SLL preset at -30 dB has been applied to design the feed of the array. Unequal T-junction dividers have been used to ensure that the output powers are proportional to the Chebyshev amplitude distribution. A reflector has been added to the back of the antenna to improve the directivity. The simulated results show that the proposed array can work at GHz with the bandwidth of 185 MHz. Moreover, it can provide the gain up to dBi and SLL suppressed to -25 dB. A prototype has also been fabricated and measured. A good agreement between simulation and measurement has been obtained. It is proved that the array can be a good candidate for point to point communications. Received 01 May 2017; Revised 20 June 2017; Accepted 27 June 2017 Keywords: Linear microstrip antenna array, Chebyshev distribution, Low sidelobe. 1. Introduction* attention from designers and researchers worldwide. Nevertheless, microstrip antenna arrays have faced the difficulty of gaining low SLL as being affected by the spurious radiation form the feeding network. Thus, in order to achieve relative SLL of 20 dB or below, the feeding network should not be on the same substrate face with the radiation patch [2]. It means that the low SLL microstrip antenna arrays must have at least two layers to distinguish the radiation element and .
