无源滤波电路的稳健优化设计

Robust Optimum Design of Passive Filter Circuit

针对实际电路系统元件参数值存在离散性以及老化、环境变化等因素使实际参数值偏离设计值而导致滤波特性改变的实际问题,建立了以系统滤波性能波动最小、元件参数值的相对容差范围最大以及参数变化时滤波性能的波动量最小的稳健优化设计数学模型.运用离散随机方向搜索、复合型等优化设计技术相结合的方式进行数值求解.应用于800MHz发射机带通滤波电路的设计中,获得了满足工程实际要求的元件参数值,给出了元件参数值的最大允许波动范围及此条件下的滤波性能的最大波动范围.对比原设计方案及容差优化设计方案,稳健优化不仅使系统的通带具有较好的平坦特性,且在元件容差较大时通带波动性也较小,即稳定性得到提高.

In view on the change of filter performance by the deviation of circuit component parameter value from its design based on the parameter＇s discreteness, eomponent＇s aging and environmental factors etc, the robust optimum design model is set up with the purpose of the minimum performance error, the maximum component tolerance and the minimum performance fluctuation at the changes of component parameter value. The optimization strategy by combining discredited random direction searching method with compound optimum is adopted for solving this optimization problem. This theory is used in an 800MHz transmitter band-pass filter circuit. It is shown by comparing the robust optimum results with optimum tolerance results that the robust optimum presented in this paper is more stable, effective and superior.