基于信道化架构的宽带I/Q不平衡校准技术

零中频接收机凭借其架构简单、易于集成等特点已被广泛应用于通信系统和雷达系统，为未来雷达通信一体化技术发展奠定了基础。然而，零中频接收机存在I/Q不平衡问题，这不仅会造成通信星座图的偏移，还会引入雷达虚假目标。现有宽带I/Q补偿方法的精度不高，且都集中于后处理，无法做到实时。因此，本文首先建立了宽带I/Q不平衡模型，并提出了一种融合信道化架构和盲估计补偿算法的宽带I/Q失衡校准技术。该技术利用信道化架构将宽带信号划分为窄带信号，并利用盲估计算法对带有镜像信号的子信道进行在线补偿。实验表明，该方法在获得高精度补偿参数的同时，完成了对宽带I/Q失衡的实时补偿。镜像抑制比达到55 dB。

Wideband I/Q Imbalance Calibration Technique Based on Channelized Architecture

The zero?IF receiver has been widely used in communication systems and radar systems due to its simple structure and easy integration, laying the foundation for the future development of radar communication integration technology. However, there is an I/Q imbalance problem in the zero?IF receiver, which not only causes the offset of the communication constellation diagram, but also introduces radar false targets. The precision of the existing wideband I/Q compensation methods is not high, and they all focus on post?processing, which cannot be realized in real time. Therefore, this paper firstly establishes a wideband I/Q imbalance model, and proposes a wideband I/Q imbalance calibration technique that combines channelization architecture and blind estimation compensation algorithm. The technique uses a channelized architecture to divide wideband signals into narrowband signals, and uses a blind estimation algorithm to perform online compensation for sub?channels with image signals. Experiments show that the method can achieve real?time compensation for wideband I/Q imbalance while obtaining high?precision compensation parameters. The image rejection ratio reaches 55 dB.