基于自适应遗传算法的低噪声放大器设计

摘要

低噪声放大器是射频接收系统的关键组成部分,决定了系统的噪声特性,直接影响接收灵敏度.提出一种利用自适应遗传算法设计低噪声放大器匹配电路的思路,自动优化交叉概率和变异概率,避免了易早熟的缺点.采用这一算法进行了放大器设计实验,放大器具有较低的噪声系数、较高的放大增益,以及较好的带外抑制效果.实验结果表明实测和软件仿真性能吻合较好,证明了自适应遗传算法设计的可靠性.%The low-noise amplifier is the key component of the RF receiving system,which determines the system noise characteristics and affects the receiving sensitivity directly. A thought of applying self-adaptive genetic algorithm to design the matching circuit of the low-noise amplifier circuit is proposed,in which the crossover and mutation probability are optimized au-tomatically to avoid the defect of premature convergence. The amplifier was designed and tested with the algorithm,which has low-noise factor,high amplifying gain and good out-of-band rejection effect. The experimental results show that the actual mea-sured result is identical with that of the software simulation greatly,and proves that the self-adaptive genetic algorithm is reliable.