Huang Jialu, Ma Hong, Jin Jiang, Zhang Hua
School of Electronic Information and Communications, Huazhong University of Science & Technology, 1037 Luoyu Road, Wuhan 430074, China.
Sensors (Basel). 2018 Apr 22;18(4):1286. doi: 10.3390/s18041286.
Recently, nonlinear blind compensation technique has attracted growing attention in array signal processing application. However, due to the nonlinear distortion stemming from array receiver which consists of multi-channel radio frequency (RF) front-ends, it is too difficult to estimate the parameters of array signal accurately. A novel nonlinear blind compensation algorithm aims at the nonlinearity mitigation of array receiver and its spurious-free dynamic range (SFDR) improvement, which will be more precise to estimate the parameters of target signals such as their two-dimensional directions of arrival (2-D DOAs). Herein, the suggested method is designed as follows: the nonlinear model parameters of any channel of RF front-end are extracted to synchronously compensate the nonlinear distortion of the entire receiver. Furthermore, a verification experiment on the array signal from a uniform circular array (UCA) is adopted to testify the validity of our approach. The real-world experimental results show that the SFDR of the receiver is enhanced, leading to a significant improvement of the 2-D DOAs estimation performance for weak target signals. And these results demonstrate that our nonlinear blind compensation algorithm is effective to estimate the parameters of weak array signal in concomitance with strong jammers.
近年来,非线性盲补偿技术在阵列信号处理应用中受到越来越多的关注。然而,由于由多通道射频(RF)前端组成的阵列接收器产生的非线性失真,准确估计阵列信号的参数非常困难。一种新颖的非线性盲补偿算法旨在减轻阵列接收器的非线性并提高其无杂散动态范围(SFDR),这将更精确地估计目标信号的参数,例如它们的二维到达方向(2-D DOA)。在此,所提出的方法设计如下:提取RF前端任何通道的非线性模型参数,以同步补偿整个接收器的非线性失真。此外,采用对来自均匀圆形阵列(UCA)的阵列信号进行验证实验来证明我们方法的有效性。实际实验结果表明,接收器的SFDR得到增强,从而显著提高了弱目标信号的二维DOA估计性能。这些结果表明,我们的非线性盲补偿算法对于在存在强干扰的情况下估计弱阵列信号的参数是有效的。