The problem of model free adaptive control (MFAC) for a class of non-affine nonlinear systems with fading measurements is investigated in this paper. The signal fading is considered to exist in output channels and this phenomenon is modeled as an independent stochastic process with a known probability distribution. The convergence of the MFAC algorithm applying the faded measurements is proved and the effects of fading phenomenon on system performance are analyzed. It is shown that the ultimate tracking error depends on the upper bound on the desired output and fading coefficient together. Then to suppress the effects of fading phenomenon, a compensated MFAC scheme with decreasing gains is proposed. The theoretical analysis shows that the improved algorithm is effective in restraining the adverse effects of fading phenomenon. Finally, a numerical example and a quadrotor attitude control example are given to illustrate the effectiveness of the proposed algorithms.

研究了一类带有衰落测量的非仿射非线性系统的无模型自适应控制（MFAC）问题。信号衰落被认为存在于输出通道中，并且这种现象被建模为具有已知概率分布的独立随机过程。证明了采用衰落测量的MFAC算法的收敛性，并分析了衰落现象对系统性能的影响。结果表明，最终的跟踪误差取决于期望输出和衰落系数的上限。为了抑制衰落现象的影响，提出了一种增益减小的补偿MFAC方案。理论分析表明，改进算法在抑制衰落现象的不利影响方面是有效的。最后，