直接耦合干扰的自适应两级补偿方法

Adaptive two-level compensating method of direct coupling interference

针对水下电磁探测系统对直接耦合干扰的补偿精度受限于硬件采样分辨率的问题,研究了基于自适应技术的直接耦合干扰两级补偿方法。采用高速DSP芯片实现直接耦合干扰补偿电路,完成直接耦合干扰的粗调补偿;提出了基于可变遗忘因子的QRD-LS算法,并采用基于该算法的自适应陷波器实现了直接耦合干扰的微调补偿。实验研究验证了两级补偿方法对直接耦合干扰的补偿性能。结果表明:基于可变遗忘因子的QRD-LS算法稳定性好,收敛速度快;基于该算法的自适应两级补偿方法对直接耦合干扰的补偿精度达到10-4倍。

As direct coupling interference compensating precision is limited by the hardware sampling resolution of the underwater electromagnetic detection system, this paper analyzes the two-level compensating method of direct coupling interference based on the adaptive technology and uses a high- speed DSP chip to compete a direct coupling interference compensating circuit for the coarse compensation. It also proposes a novel QRD-LS algorithm based on the variable forgetting factor. According to the algorithm, an adaptive notch filter is used to make the trimming compensation for the direct coupling interference. Through experiments, the two-level method is proved to be effective direct coupling interference compensation. The results show that the QRD-LS algorithm based on the varia- ble forgetting factor has advantages of high stability and fast convergence, so that the adaptive twolevel compensating method based on this algorithm reaches a 10 4 times in precision for the direct cou- pling interfe-rence compensation.