Blind I/Q imbalance parameter estimation and compensation in low-IF receivers
Blind I/Q imbalance parameter estimation and compensation in low-IF receivers
复制标题
低中频接收器中的盲 I/Q 不平衡参数估计和补偿
DOI：
10.1109/isccsp.2004.1296222
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发表时间：
2004
期刊：
影响因子：
--
通讯作者：
G. Fettweis
中科院分区：
文献类型：
--
作者：
M. Windisch;G. Fettweis
镜像信号的抑制是所有接收器架构固有的问题。低中频接收器的优点之一是，镜像抑制是通过 I/Q 信号处理而不是固定的模拟滤波器来实现的，从而使其具有高度可重新配置性和成本效益。然而，I 和 Q 分支之间不可避免的不平衡会导致有限的图像衰减。本文提出了一种新颖的 I/Q 不平衡补偿方案，其中未知的模拟不平衡参数以数字方式估计，而不需要任何校准或训练信号。基于这些估计，图像信号的干扰得到了有效补偿，将脆弱的普通低中频接收器升级为强大的先进接收器架构，其中图像信号比的平均值永远不会超过预定义的最大值，无论图像信号功率如何。
The rejection of the image signal is a problem inherent to all receiver architectures. One of the benefits of the low-IF receiver is, that image rejection is realized by I/Q signal processing instead of a fixed analog filter, making it highly reconfigurable and cost-efficient. However, unavoidable imbalances between the I- and Q-branch lead to a limited image attenuation. In this paper a novel I/Q imbalance compensation scheme is presented, in which the unknown analog imbalance parameters are estimated digitally without the need for any calibration or training signal. Based on these estimates the interference by the image signal is effectively compensated, upgrading the vulnerable ordinary low-IF receiver to a powerful advanced receiver architecture, where the mean value of the image-to-signal ratio never exceeds a pre-defined maximum value, regardless of the image signal power.