基于CRLH-TL零阶谐振特性的新型串联功分器

Novel series power divider based on zeroth-order resonance of composite right left-handed transmission line

结构紧凑的功分器是微波信号分离、阵列天线馈电等应用场合的重要器件。利用混合右／左手传输线（CRLH-TL）来设计小尺寸的串联功分器，并对混合右／左手传输线的色散特性进行理论分析。利用贴片电容和微带线电感设计了一种新的混合右／左手传输线，处于零阶谐振状态的混合右／左手不引入相位偏移且波长为无穷大。基于CRLH-TL的零阶谐振特性设计制作了一个工作在2.45GHz的4路微波功分器。此功分器等幅同相地将输入功率分配到各个输出端口，输出端口位置对功率分配没有影响。使用矢量网络分析仪对该功分器进行了实验测量，结果表明：在2.20～2.65GHz的频率范围内，功分器各输出端口功率相差在1dB内；在2.22～2.56GHz的频率范围内，输出端口的相位差在15°以内。测量结果与仿真结果吻合良好。该微波功分器结构紧凑，可扩展到任意多个输出端口。

Compact power divider is a crucial part in microwave signal dividing and antenna array feeds. A composite right/left-banded transmission line （CRLH-TL） was applied to design of a small-size series power divider and theoretic analysis of its dispersion characteristics was conducted. A novel CRLH-TL by utilizing chip capacitors and micro-strip inductors was presented. The CRLH-TL at zero-order resonant frequency does not induce phase shift and supports an infinite wavelength, and then based on its vibrating properties, a 4 series microwave power divider working at 2.45 Hz was designed and manufactured. This divider equally divided input power to each output port and the position of output port bad no influence on it. The manufactured divider was measured by a vector network analyzer. The magnitude difference between output ports is less than 1 dB from 2.20 GHz to 2. 65 GHz,and the phase difference between output ports is less than 15° from 2. 22 GHz to 2. 56 GHz. The measured results well accord with the simulated results. In addition, this divider is very compact and flexible, and can be extended to an random number of output ports.