For a large-scale adaptive array, the heavy computational load and the high-rate data transmission are two challenges in the implementation of an adaptive digital beamforming system. An efficient parallel digital beam...For a large-scale adaptive array, the heavy computational load and the high-rate data transmission are two challenges in the implementation of an adaptive digital beamforming system. An efficient parallel digital beamforming (DBF) algorithm based on the least mean square algorithm (PLMS) is proposed. An appropriate method is found to partition the least mean square (LMS) algorithm into a number of operational modules, which can be easily executed in a distributed-parallel-processing fashion. As a result, the proposed PLMS algorithm provides an effective solution that can alleviate the bottleneck of high-rate data transmission and reduce the computational cost. PLMS requires less computational load than that of the conventional parallel algorithms based on the recursive least square (RLS) algorithm, as well as it is easier to be implemented to do real time adaptive array processing. Moreover, low sidelobe of the beam pattern is obtained by constraining the static steering vector with Tschebyscheff coefficients. Finally, a scheme of the PLMS algorithm using distributed-parallel-processing system is also proposed. The simulation results demonstrate that the PLMS algorithm has the same interference cancellation performance as that of the conventional LMS algorithm. Moreover, the PLMS algorithm can obtain the same good beamforming performance, regardless how the algorithm is partitioned. It is expected that the proposed algorithm will be used in a large-scale adaptive array system to deal with real time adaptive digital beamforming processing.展开更多
The adaptive array antenna may be considered as a general sidelobe canceller. Directional interference suppression is based on a recursive state estimation of Kalman filter. For the stationary filter,this leads to an...The adaptive array antenna may be considered as a general sidelobe canceller. Directional interference suppression is based on a recursive state estimation of Kalman filter. For the stationary filter,this leads to an iterative solution of Wiener Hops matrix equation. The performance of sidelobe canceller are studied by computer simulation. The result of simulation shows that the sidelobe canceller may be regarded as a special case of an adaptive array atenna.展开更多
在复杂的语音环境中,利用麦克风阵列语音增强技术能有效地拾取目标语音信号并消除噪声干扰,但传统的麦克风阵列波束形成的加权系数是固定的.为了能灵活地控制麦克风阵列波束的形成方向以及消除其波束旁瓣带来的残余噪声,提出了一种基于...在复杂的语音环境中,利用麦克风阵列语音增强技术能有效地拾取目标语音信号并消除噪声干扰,但传统的麦克风阵列波束形成的加权系数是固定的.为了能灵活地控制麦克风阵列波束的形成方向以及消除其波束旁瓣带来的残余噪声,提出了一种基于麦克风阵列的自适应语音增强技术.该技术将自适应滤波器和麦克风阵列相结合形成波束可控的广义旁瓣消除器,然后在广义旁瓣消除器后面续接一个改进的谱减法,并加入契比雪夫窗函数.仿真实验结果表明,所提出的语音增强方法能有效去除语音信号中的噪声干扰,相比于传统广义旁瓣消除器,信噪比大约提高了3.5 d B.展开更多
文摘For a large-scale adaptive array, the heavy computational load and the high-rate data transmission are two challenges in the implementation of an adaptive digital beamforming system. An efficient parallel digital beamforming (DBF) algorithm based on the least mean square algorithm (PLMS) is proposed. An appropriate method is found to partition the least mean square (LMS) algorithm into a number of operational modules, which can be easily executed in a distributed-parallel-processing fashion. As a result, the proposed PLMS algorithm provides an effective solution that can alleviate the bottleneck of high-rate data transmission and reduce the computational cost. PLMS requires less computational load than that of the conventional parallel algorithms based on the recursive least square (RLS) algorithm, as well as it is easier to be implemented to do real time adaptive array processing. Moreover, low sidelobe of the beam pattern is obtained by constraining the static steering vector with Tschebyscheff coefficients. Finally, a scheme of the PLMS algorithm using distributed-parallel-processing system is also proposed. The simulation results demonstrate that the PLMS algorithm has the same interference cancellation performance as that of the conventional LMS algorithm. Moreover, the PLMS algorithm can obtain the same good beamforming performance, regardless how the algorithm is partitioned. It is expected that the proposed algorithm will be used in a large-scale adaptive array system to deal with real time adaptive digital beamforming processing.
文摘The adaptive array antenna may be considered as a general sidelobe canceller. Directional interference suppression is based on a recursive state estimation of Kalman filter. For the stationary filter,this leads to an iterative solution of Wiener Hops matrix equation. The performance of sidelobe canceller are studied by computer simulation. The result of simulation shows that the sidelobe canceller may be regarded as a special case of an adaptive array atenna.
文摘在复杂的语音环境中,利用麦克风阵列语音增强技术能有效地拾取目标语音信号并消除噪声干扰,但传统的麦克风阵列波束形成的加权系数是固定的.为了能灵活地控制麦克风阵列波束的形成方向以及消除其波束旁瓣带来的残余噪声,提出了一种基于麦克风阵列的自适应语音增强技术.该技术将自适应滤波器和麦克风阵列相结合形成波束可控的广义旁瓣消除器,然后在广义旁瓣消除器后面续接一个改进的谱减法,并加入契比雪夫窗函数.仿真实验结果表明,所提出的语音增强方法能有效去除语音信号中的噪声干扰,相比于传统广义旁瓣消除器,信噪比大约提高了3.5 d B.