基于FPGA和DSP的DBF实现

The Realization of Digital Beamforming Based on FPGA and DSP

FPGA和DSP通过带通采样、I/Q支路的数字化和数字滤波进而实现基带信号数字波束合成(DBF)。为了更加合理地利用各种现代电子开发工具来充分发挥DSP突出的运算能力,以及FPGA逻辑处理能力强、速度快的优点,可将二者结合使用。在FPGA中,首先利用高速高精度AD对中频调制信号进行带通采样,然后利用DDS对采集数据进行I/Q分解并用数字滤波器进行滤波,然后对滤波后数据进行加权求和从而实现系统功能。在DSP中,主要进行波达方向估计,并用直接矩阵求逆算法计算权值。实验结果表明,该方法硬件简单,软件配置灵活,并且性能良好,能很好的满足应用需要。

FPGA and DSP make the realization of signal beam forming（DBF） for baseband signal through band-pass sampling,I/Q digital branch decomposition and digital filtering.In order to make more rational use of modern electronic tools,make full use of DSP＇s computing power,give prominence to FPGA＇s strong logic processing capacity and fast speed,a combination of both will be used.In the FPGA,firstly band-pass sample the intermediate frequency modulated signal using high-speed high-precision frequency Ads;next,adopt DDS to conduct I/Q decomposition on the collected data and then filter it through the digital filter;finally weight and sum the filtered data and system function is achieved.While,the main work of DSP is to estimate the DOA and calculate the needed weights by the algorithm of matrix inversion.Experimental results show that,the hardware1 design is straightforward,the software does have a good flexibility in configuration,and the system adapt well in application needs.