Guo Qiang, Qi Liangang
College of Information and Communication Engineering, Harbin Engineering University, Harbin 150001, China.
Sensors (Basel). 2017 Apr 10;17(4):813. doi: 10.3390/s17040813.
In the coexistence of multiple types of interfering signals, the performance of interference suppression methods based on time and frequency domains is degraded seriously, and the technique using an antenna array requires a large enough size and huge hardware costs. To combat multi-type interferences better for GNSS receivers, this paper proposes a cascaded multi-type interferences mitigation method combining improved double chain quantum genetic matching pursuit (DCQGMP)-based sparse decomposition and an MPDR beamformer. The key idea behind the proposed method is that the multiple types of interfering signals can be excised by taking advantage of their sparse features in different domains. In the first stage, the single-tone (multi-tone) and linear chirp interfering signals are canceled by sparse decomposition according to their sparsity in the over-complete dictionary. In order to improve the timeliness of matching pursuit (MP)-based sparse decomposition, a DCQGMP is introduced by combining an improved double chain quantum genetic algorithm (DCQGA) and the MP algorithm, and the DCQGMP algorithm is extended to handle the multi-channel signals according to the correlation among the signals in different channels. In the second stage, the minimum power distortionless response (MPDR) beamformer is utilized to nullify the residuary interferences (e.g., wideband Gaussian noise interferences). Several simulation results show that the proposed method can not only improve the interference mitigation degree of freedom (DoF) of the array antenna, but also effectively deal with the interference arriving from the same direction with the GNSS signal, which can be sparse represented in the over-complete dictionary. Moreover, it does not bring serious distortions into the navigation signal.
在多种干扰信号共存的情况下,基于时域和频域的干扰抑制方法性能会严重下降,而使用天线阵列的技术需要足够大的尺寸和高昂的硬件成本。为了让全球导航卫星系统(GNSS)接收机更好地对抗多类型干扰,本文提出了一种级联多类型干扰缓解方法,该方法将基于改进的双链量子遗传匹配追踪(DCQGMP)的稀疏分解与MPDR波束形成器相结合。所提方法背后的关键思想是,利用多种干扰信号在不同域中的稀疏特征将其去除。在第一阶段,根据单音(多音)和线性调频干扰信号在过完备字典中的稀疏性,通过稀疏分解将其消除。为了提高基于匹配追踪(MP)的稀疏分解的时效性,通过结合改进的双链量子遗传算法(DCQGA)和MP算法引入了DCQGMP,并根据不同通道信号之间的相关性将DCQGMP算法扩展以处理多通道信号。在第二阶段,利用最小功率无失真响应(MPDR)波束形成器消除残留干扰(如宽带高斯噪声干扰)。若干仿真结果表明,所提方法不仅可以提高阵列天线的干扰缓解自由度(DoF),还能有效处理与GNSS信号来自同一方向且能在过完备字典中稀疏表示的干扰。此外,它不会给导航信号带来严重失真。