自适应回声抵消是消除助听器回声啸叫的有效方法. 针对回声路径评估偏差大的问题，文中提出线性预测-并行梯度投影算法，通过对助听器输出信号进行线性预测来生成解相关FIR 滤波器，获得解相关信号. 系统利用解相关信号构建包含回声路径的凸优化方程，并设计并行梯度投影算法求解该方程，实现回声路径的估计. 实验结果表明算法在收敛速度、稳定性和精度等方面改进显著.

 Adaptive feedback cancellation is an effective way to suppress echo howling in hearing aids. However,when the external input signal is correlated with the receiver input signal, the estimate of the feedback path contains a large error. This paper proposes a linear prediction-parallel gradient projection algorithm,which generates a FIR filter to obtain the decorrelation signal by linear prediction of the output signals. The decorrelation signal is then used to build a convex optimization equation. With the parallel gradient projection algorithm, the equation is solved to evaluate the echo path. Simulation results show clear improvement in convergence, stability and precision.