小型阵列宽带恒定束宽波束形成器仿真研究  

Broadband Constant Beamwidth Beamforming Technology Based on Compact Array

作　　者：张天伟[1] 陈航[1] 马存宝[1] 宋东[1] 

机构地区：[1]西北工业大学,陕西西安710072

出　　处：《计算机仿真》2013年第5期181-186,共6页Computer Simulation

摘　　要：关于优化宽带恒定束宽波束形成,是阵列小型化和对低频宽带信号探测的核心问题。为了研究阵元间距小于四分之一波长的线列阵的宽带恒定束宽波束形成器设计,提出了FIR滤波器的适用于小型传感器阵列的时域恒定束宽波束形成方法,分析了频域和时域宽带波束形成的特点,进行了时域宽带恒定束宽波束形成器的设计。根据最小均方准则,求出了频域子带波束形成加权向量,使工作频带内各子带波束主瓣趋近于期望波束,同时控制工作频带内波束旁瓣响应幅度,波束图主瓣形状设计与期望频率响应FIR滤波器的设计问题都转化为二阶锥规划方法,从而实现工作频带内的恒定主瓣束宽。通过仿真证明,改进方法可使密排阵列在2000Hz～4000Hz工作频段范围内具有恒定束宽的方向特性。This paper studies the directivity pattern of the miniaturized linear array. The element spacing is less than a quarter wavelength. A method of broadband constant beamwidth beamforming （BCBB） based on finite impulse response （FIR） filters was presented. The existing DFT domain beamforming methods were review, and its character- istics were analysed. The wideband constant beam width beamformer was designed in time domain. Firstly, we de- signed the subband beamforming weighting vector, using optimization method for beam pattern optimization design, so that the working frequency band of each subband beam main lobe approaches the desired beam, while controlling the response amplitude of the sidelob~. Both the design of beamformers and that of FIR filters can be converted to a con- vex optimization form as the so-called Second-Order Cone Programming （SOCP） , thereby realizing the band con- stant beamwidth in working frequency. This method can make a miniaturized linear array with constant beam width di- rection characteristic in 2000Hz -4000Hz working frequency range.

关 键 词：密排线列阵 方向性图 恒定束宽 波束形成 

分 类 号：TP391.9[自动化与计算机技术—计算机应用技术]