A Dual-Frequency 0.7-to-1GHz Balance Network for Electrical Balance Duplexers

📋 论文概要

该论文提出了一种用于电气平衡双工器的双频平衡网络，工作频率0.7-1GHz，旨在解决FDD移动系统中在TX和RX两个频率上同时平衡天线阻抗的挑战。通过片上可调阻抗实现双频段隔离，适用于4G/5G移动系统。

💡 主要创新点

• 提出双频平衡网络结构，能在两个不同频率（TX和RX）上同时实现阻抗平衡，克服传统单频平衡网络的局限性。
• 工作频率覆盖0.7-1GHz，支持多个4G/5G频段，且采用片上可调阻抗实现，提高集成度和灵活性。

🏷 关键词

📄 原文摘要

seeks to address several key challenges of 4G and 5G mobile systems [1]. The basic principle is shown in Fig. 20.8.1. Duplexer isolation is achieved when the signals in paths 1 and 2 cancel and prevent the TX signal from appearing at the RX port. This cancellation is achieved by “balancing” the antenna impedance ZANT with an on-chip tunable impedance ZBAL. In frequency-division duplex (FDD) mobile applications, ZBAL is the most challenging and critical sub-block in an EBD design. FDD TX and RX channels are always at separate frequencies, and ZBAL must be able to balance the antenna at both, simultaneously. Moreover, the antenna impedance varies over time due to user interaction, and must be tracked by the balance network.

👥 作者与机构

Benjamin Hershberg1, Barend van Liempd1,2, Xiaoqiang Zhang1,

Piet Wambacq1,2, Jan Craninckx1 imec, Heverlee, Belgium, 2Vrije Universiteit Brussel, Brussels, Belgium 1 An electrical-balance duplexer (EBD) is a tunable RF front-end concept that