的具有高信号隔离的四端口双模双工器的易于被呈现。与Rx和Tx模块之间的高信号隔离的紧凑双模双工器通过仅使用一个谐振器滤波器的拓扑结构是可以实现的。两回到后端双模双工器具有在一个支路中的180°相移。高隔离度可以通过振幅和相位消除技术来实现。延迟传输线可以通过移相器可以容易地实现。ŤHe simulated and measured four-port dual-mode diplexers are designed at the centre frequency of Rx/Tx at 1.95 GHz and 2.14 GHz, respectively. The measured results of Rx/Tx dual-mode diplexer devices are presented with 47.1 dB Rx/Tx isolation. This four-port dual-mode diplexer achieves the isolation (
小号GydF4y2Ba32GydF4y2Ba)of more than 24.1 dB when compared with the conventional three-port dual-mode diplexer structure.
开路短线(GydF4y2Ba
žGydF4y2Ba2GydF4y2Ba)连接到所述谐振器的中间(GydF4y2Ba
žGydF4y2Ba1GydF4y2Ba)。GydF4y2Ba
αZGydF4y2Ba2GydF4y2Ba表示与阻抗部分的偶模阻抗等效GydF4y2Ba
žGydF4y2Ba2GydF4y2Ba。的电气长度(GydF4y2Ba
θGydF4y2Ba2GydF4y2Ba开路短截线的)可以从被定义GydF4y2Ba
(2)GydF4y2Ba
θGydF4y2Ba
1GydF4y2Ba
≅GydF4y2Ba
πGydF4y2Ba
-GydF4y2Ba
CGydF4y2Ba
4GydF4y2Ba
FGydF4y2Ba
奇GydF4y2Ba
εGydF4y2Ba
EFFGydF4y2Ba
,GydF4y2Ba哪里GydF4y2Ba
θGydF4y2Ba
XGydF4y2Ba(GydF4y2Ba
XGydF4y2Ba = 1, 2, 3) corresponds to the electrical length of the section in Figure
1GydF4y2Ba和GydF4y2Ba
CGydF4y2Ba是光在真空中的速度。GydF4y2Ba
为了证明所提出的双模微带线滤波器,谐振器是GydF4y2Ba
üGydF4y2Ba形状,其由前端开路短截线加载。该过滤器被设计具有一定厚度的RT /的Duroid基板上GydF4y2Ba
HGydF4y2Ba = 1.27 mm with a relative dielectric constant
εGydF4y2Ba
[RGydF4y2Ba = 6.15. The filters were simulated by IE3D full-wave EM simulations. The input and output coupled-feed lines are used to couple the signal to the dual-mode resonator having a line width (cf) and coupling spacing (
GGydF4y2Ba)。奇数和偶数模式被称为前两个谐振模式。这两种模式可以具有依赖于开路短截线的长度相同或不同的模态频率。一个双模式谐振器的微带的基本结构在图被描绘GydF4y2Ba
4GydF4y2Ba。GydF4y2Ba
与输入/输出的双模式谐振器的微带的示意性结构耦合进料。GydF4y2Ba
相比于第一寄生模式的工作频率通过调谐开路短截线的长度一直使用IE3D全波EM仿真研究。双模式谐振器被设计为通过固定的长度以实现期望的共振频率GydF4y2Ba
üGydF4y2Ba形谐振器(a和c)。偶模式特性可以通过调节开路短截线的长度来实现加载(b)中。Ťw ^o input/output microstrip lines with 50 Ω characteristic impedance are used to feed the proposed dual-mode resonator with open-stub loaded resonator. As can be seen in Figure
五GydF4y2Ba,开短装载长度,不影响GydF4y2Ba
小号GydF4y2Ba21GydF4y2Ba响应在奇数模式的谐振频率,而偶数模式的谐振频率通过改变开路短截线(B)的长度被灵活控制。固有的传输零点(TZ)可以容易地调节,以优化的响应。的TZ导致不对称的响应。当谐振器被耦合到与一耦合馈电结构的输入和输出端口,前两个谐振模被称为奇数和偶数模式。这两种模式可以具有相同的或不同的模态频率取决于在谐振器的尺寸。此外,当两个模式分割,有限传输零点是在两种模式中的高侧时产生的偶数模式的频率是比奇数模式频率高。此属性的主要成果是滤波器实现具有非对称的频率响应(滤波器的上阻带)。GydF4y2Ba
位于与装载开路短截线的长度不同的工作频率的上侧传输零点的模拟响应。GydF4y2Ba
1.2。四端口双模双工器的设计GydF4y2Ba
所提出的四端口微带双模双工器的布局结构呈现于图GydF4y2Ba
图6(a)GydF4y2Ba。ŤHe Tx/Rx filters are interconnected by an appropriately designed matching circuit of T-junction that has the width of the 50 Ω line. The diplexer geometry is optimized at the T-junction for better return loss performance in both the channels. It is noted that using port 1 with an impedance of 50 Ω as the feed line has advantages of obtaining better diplexer insertion loss and rejection performances. Here, the lengths of the T-junction are optimized such that each filter in the diplexer should look like an open circuit to the other filter at its centre frequency.
测量进行使用Agilent矢量网络分析仪。四端口双模双工器的测量和模拟的结果示于图GydF4y2Ba
图7(a)GydF4y2Ba。ŤHe measured in-band return loss is better than 25 dB in the first bandpass (1.95 GHz) and 24 dB in the second bandpass (2.14 GHz), respectively. The insertion losses are approximately 1.1/1.16 dB at the two bandpasses. The simulation and measurement results are in good agreement. The comparison of signal isolation,
小号GydF4y2Ba32GydF4y2Ba的Rx和Tx频带之间的四端口双模双工器和三端口双模式双工器隔离的示于图GydF4y2Ba
图7(b)GydF4y2Ba。ŤHe measured signal isolation of the conventional three-port dual-mode diplexer is 23 dB, and it is 47.1 dB for the four-port dual-mode diplexer. The excess losses in the measurements are believed to be due to the SMA connectors and fabrication errors.
具有高信号隔离的四端口双模双工器基于振幅和相位消除技术被呈现。用Tx和Rx模块之间的高信号隔离的小型双模式带通滤波器仅通过使用一个谐振器滤波器的拓扑结构是可以实现的。两回到后端双模双工器具有在一个支路中的180°相移。高隔离度可以通过振幅和相位消除技术来实现。延迟传输线可以通过移相器可以容易地实现。四端口微带双模双工器可以提升隔离(GydF4y2Ba
小号GydF4y2Ba32GydF4y2Ba)Ťo more than 24.1 dB from the conventional three-port diplexer. Finally, the low complexity design and ease of fabrication process are proposed by using a four-port dual-mode diplexer which can be used in wireless communications.