采用CIC（级联积分梳状）滤波器实现降采样的功能，并分析了级联级数、差分延时数对CIC滤波器幅频响应的影响；采用Verilog语言实现了CIC滤波及降采样的功能；-Using CIC (Cascaded Integrator Comb) filter down-sampling function, and analyzes cascaded stages, affecting the number of differential delay CIC filter amplitude-frequency response　using Verilog language of the CIC filter and down sampling Features