基于改进仿射投影算法的数字助听器自适应回声消除

提出了一种改进的仿射投影算法。该算法建立了步长因子与误差能量之间一种新的非线性函数关系，根据误差能量的变化自动调整步长因子，以达到加快滤波器收敛速度、降低稳态失调的目的；在对误差能量的估计中提出了遗忘因子选择规则，提高了误差能量估计的准确性。对提出的算法进行的数学分析，为其快速收 敛性提供了理论依据。实验仿真表明，与传统的自适应算法以及固定步长的仿射投影算法相比，提出的改进仿射算法在收敛速度、稳态失调等方面有明显改善。

Acoustic Feedback Cancellation Based on Improved Affine Projection Algorithm for Hearing Aids

An improved affine projection algorithm for hearing aids is proposed to increase the convergence speed and reduce the misalignmengt. The algorithm establishes a new nonlinear function between the step-size and the estimation error. The step-size of the proposed algorithm is adjusted automatically according to the change of the estimation error, which leads to high convergence speed and low misalignment. In order to improve the accuracy of estimating the power of error, a rule for selecting forgetting factor is proposed. Mathematical analysis provides theoretical basis for its outstanding capacity of converging to the objective system. The simulation results show that the proposed algorithm achieves faster convergence speed and lower final misalignment compared with traditional adaptive methods and fixed step-size affine projection algorithm.