在弹载测控系统地磁检测的背景下,针对传统硬件滤波的缺点,提出了一种基于FPGA芯片的滤波处理方法。根据地磁采样数据的性能指标,通过Matlab计算出满足要求的滤波器结构与系数,利用Verilog语言完成FPGA的板级设计。并针对IIR滤波器非线性的特性,设计出一种基于相频响应曲线的相位补偿方法,实现了信号的线性跟随。实验证明,基于FPGA的滤波处理运算速度快,系数改变灵活,滤波效果好,具备良好的实用性。

Against the background of magnetic detection of missile-borne control system, a new filtering method which based on FPGA was expounded due to shortcoming of traditional hardware filtering. According to the performance specification of geomagnetic data, structure and coefficients which meet the requirements of filter were designed by Matlab, and Verilog was used to complete board-level design of FP-GA. According to nonlinear characteristics of IIR filter, a phase compensation method based on phase-frequency response was put forward. Experiment has proved that filtering method based on FPGA has advantages of high speed of operation, flexible control, better filtering effect and good practicability.