适用于天线失配修正的自适应匹配网络(英文)

Adaptive Matching Network for Antenna Mismatch Correction

在无线信号传输链路中,功率放大器是最耗能的器件之一,无论是在正常工作模式下还是在天线失配的情况下,功率放大器的效率一直是设计的重要考量.特别在天线失配的情况下,呈现在功率放大器输出端不断变化的失配天线负载情况将会使功率放大器的效率严重恶化.对适用于天线失配修正的基于可变电容构建的自适应匹配网络进行了可行性分析,重点对基于LC谐振腔所设计的Π型匹配网络从功率增益、史密斯圆图覆盖率和可变电容有效调谐范围几个方面进行了性能优化.分析表明,在自适应匹配网络的帮助下,全角度变化VSWR=10表征的天线失配情况可以被修正到所需的理想负载匹配情况(ΓLstage=0),以保证功率放大器工作在高效模式下,由此功率放大器获得了明显的效率提升和线性度改善.

The power amplifier is generally considered to be one of the most power-hungry components in the transceiver. Therefore its efficiency is major point of concern, not only in normal operation but also in the presence of antenna mismatch, when the varying load offered to power amplifier stage can result in severe efficiency degradation. The feasibility of a varactor-based adaptive matching network for antenna mismatch correction is investigated. A LC-resonator-based H-section network is optimized for its performance, in terms of operation power gain, Smith Chart coverage, and effective capacitance tuning range of the varactors. It is shown that mismatch loading conditions, with a voltage standing wave ratio （VSWR） of 10, can be properly corrected back to the optimal matching condition （ГLstage = 0）, while providing a relatively high linearity and operating power gain, which ensures the high efficiency operation of the power amplifier.