Wide Null Array Antenna Desig

The null steering technique is an anti-jamming method that can aim the null beam at the interference to eliminate the impact of the interference.However,the interference source is usually in fast movement,so the null steering antenna has a high requirement for null range coverage.In this paper,the extended method of minimum power transmission efficiency(EMMPTE)is used to wide null steering of antenna array and propose a wide null steering method with the direction and width of the null can be adjustable.The main research of this paper includes:1.First,a one-dimensional narrow-band array antenna operating at 3.4 GHz is designed,which is composed of 8 microstrip patch antenna units in a linear arrangement.Equating the antenna far-field null range to several electric field power nulls.Based on the Extended MMPTE,the optimal excitation distribution of the antenna array forming a wide null beam is obtained.An 8-port digital RF feed network for antenna feeding is designed.The simulation and test results show that the one-dimensional narrow-band nulling antenna array can realize the flexible control of null direction and width in the whole forward radiation region,and the null depth is greater than-20 d B.2.Then,in order to verify applicability of the Extended MMPTE,a broadband antenna array working at 2 ～ 6 GHz is designed.The antenna array consists of 8 Vivaldi antenna units arranged along the H-plane and select several frequency points of the broadband antenna array for wide null steering demonstration.Similarly,the null range of the far field area of the antenna array is equivalent to several electric field power null points,and the Extended MMPTE is used to calculate the antenna array excitation distribution,so as to realize the wide null beam of the broadband antenna array.The simulation and test results show that the wide null steering of broadband antenna array can achieve arbitrary control of the wide null in the whole forward radiation region at any frequency point within the operating bandwidth.