Novel Ultra-Wideband (UWB) Multilayer Slotline Power Divider With Bandpass Response

A novel ultra-wideband (UWB) multilayer slotline power divider with bandpass filtering response is presented. In the proposed structure, a single isolation resistor is properly placed between the two output ports. Based on the transmission-line equivalent-circuit method, the design equations of the proposed UWB power divider has been derived with the even and odd mode analyses. Experimental results show that excellent impedance matching at all three ports, amplitude and phase balance at the two output ports, isolation between the two output ports, and out-of-band rejection are observed at the UWB band.      

A Parallel-Strip Ring Power Divider With High Isolation and Arbitrary Power-Dividing Ratio

In this paper, a new power divider concept, which provides high flexibility of transmission line characteristic impedance and port impedance, is proposed. This power divider is implemented on a parallel-strip line, which is a balanced transmission line. By implementing the advantages and uniqueness of the parallel-strip line, the divider outperforms the conventional divider in terms of isolation bandwidths. A swap structure of the two lines of the parallel-strip line is employed in this design, which is critical for the isolation enhancements. A lumped-circuit model of the parallel-strip swap including all parasitic effects has been analyzed. An equal power divider with center frequency of 2 GHz was designed to demonstrate the idea. The experimental results show that the equal power divider has 96.5% -10-dB impedance bandwidth with more than 25-dB isolation and less than 0.7-dB insertion loss. In order to generalize the concept with an arbitrary power ratio, we also realize unequal power dividers with the same isolation characteristics. The impedance bandwidth of the proposed power divider will increase with the dividing ratio, which is opposite to the conventional Wilkinson power divider. Unequal dividers with dividing ratios of 1 : 2 and 1 : 12 are designed and measured. Additionally, a frequency independent 180 power divider has been realized with less than 2 phase errors.     

An Ultra-Wideband Bandpass Filter With an Embedded Open-Circuited Stub Structure to Improve In-Band Performance

In this letter, we present a compact ultra-wideband bandpass filter (BPF) with a notch band in the BPF performance by using an embedded open-circuited stub structure. The filter mainly consists of conventional stepped impedance resonator (SIR) as the multiple-mode resonator and two enhanced coupled input/output lines. The bandwidth can be analyzed by using the image-parameter method to obtain the proper dimension of the coupled lines and verified by using electromagnetic (EM) simulation. The embedded open-circuited stub structure in the SIR is used to produce a narrow notched band at 5.8 GHz, which its frequency position and bandwidth can be tuned by its physical parameters. The measured 3 dB fractional bandwidth of 113.8% and narrow notched band with 25 dB rejection is achieved. Good agreement between the EM simulation and measurement is obtained.      

Novel Filtering Power Divider with External Isolation Resistors

In this paper, a novel filtering power divider with external isolation resistors is presented. The proposed power divider can be considered as an integration of a bandpass filter and a Gysel power divider. Based on the circuit topology, a high‐order filtering power divider can be easily realized. Odd‐ and even‐mode models are employed to analyze the filtering and power splitting functions. For demonstration, a third‐order filtering power divider operating at 1.5 GHz is designed and implemented. The measured results exhibit an isolation between the output ports that is better than 20 dB at around the center frequency.     

一种微带线高隔离度功分器的设计

在功分器设计中,随着频率的升高,输出端口的隔离度会变差,使系统性能下降。应某课题的需求,利用微 带传输线的特性,仿真设计了一种具有高隔离度的Ku 频段威尔金森功分器,设计原理是通过在输出臂适当增加微带线, 同时引入隔离电阻实现输出端口匹配。将此功分器应用到阵列天线的馈电系统,子天线间端口隔离度变大,仿真结果 能达到-40dB,能够满足应用需求,提升了阵列天线系统的性能。     

Miniaturized Microstrip Wilkinson Power Divider With Harmonic Suppression

A microstrip Wilkinson power divider with harmonic suppression and size reduction is presented in this letter. The proposed power divider not only effectively reduces its occupied area to 36.5% of the conventional design at 2.65 GHz but also has higher order harmonics suppression. From the measured results, a 29 dB suppression for the third harmonic and a 34 dB suppression for the fifth harmonic are achieved while maintaining the characteristics of a conventional Wilkinson power divider. Based on a 15 dB return-loss criteria, the measured fractional bandwidth is 48%. At an operation frequency of 2.65 GHz, the insertion losses are better than 3.4 dB, the return loss is 27 dB, and the isolation is better than 22 dB.      

Ka-band Wide-Isolation-Bandwidth Waveguide Power Divider Using Microstrip-Probe Isolation Circuit

Journal of Infrared, Millimeter, and Terahertz Waves - A Ka-band wide-isolation-bandwidth waveguide power divider using a microstrip-probe isolation circuit is proposed in this paper. A novel...     

Eight-Way Substrate Integrated Waveguide Power Divider With Low Insertion Loss

We describe a compact radial cavity power divider based on the substrate integrated waveguide (SIW) technology in this paper. The equivalent-circuit model is used to analyze the multiport structure, and a design procedure is also established for the structure. An eight-way C-band SIW power divider with low insertion loss is designed, fabricated, and measured. Good agreement between simulated and measured results is found for the pro posed power divider. The measured minimum insertion loss of the eight-way power divider is approximately 0.2 dB and return loss is approximately 30 dB at 5.25 GHz. The measured 15-dB return-loss bandwidth is found to be approximately 500 MHz, and its 1-dB insertion-loss bandwidth is approximately 1.2 GHz. Furthermore, the isolations between the output ports of the eight-way power divider are also discussed.     

A Dual-Band Unequal Wilkinson Power Divider With Arbitrary Frequency Ratios

This letter presents a theoretically rigorous investigation and experimental verification for an asymmetrical, unequal power divider working at dual frequency bands. Through the even- and odd-mode analysis that can be applied to dual-band, unequal power divider by assuming virtual open and short points, analytically exact solutions have been derived for the design parameters values. For verification of this analysis, commercially available software including ADS and CST MWS based on circuit theory and full-EM theory, respectively, and already-established equations have been adopted.      

基于Ansoft Designer仿真工具的高隔离度MIC功率分配器

主要介绍了用Ansoft Designer设计的耦合型功率分配器,对用Ansoft Designer设计的电路进行了分析,并采用弧形修正方式补偿阶梯突变所产生的不连续,最后给出了其仿真结果。     

Compact and Harmonic Suppression Wilkinson Power Divider With Short Circuit Anti-Coupled Line

A compact Wilkinson power divider using a short circuit anti-coupled line for harmonic suppression is presented in this letter. The structure consists of a pair of anti-coupled line short circuited by a capacitive load realized by a low impedance line. It can offer three finite attenuation poles in the stopband, while arbitrary phase shift can be obtained in the passband. Design procedures have been clearly presented. A 1.8-GHz power divider is designed, fabricated and measured for demonstration. It agreed well with the simulated results. The circuit area of the proposed divider is only 40% of that of the conventional one. Furthermore, the proposed divider has spurious pass-band suppression as high as 20dB.     

Ka-Band Rectangular-Waveguide Gysel Power Divider with Low Insertion Loss and High Output Isolation

A Ka-band Gysel power divider based on rectangular waveguide is presented in this paper. The model and equivalent circuit of the presented power divider is introduced. The even- and odd-mode analytical method is applied to analyze the equivalent circuit. A Ka-band waveguide Gysel power divider is designed, optimized, fabricated, and measured. Good agreement between the simulated and measured results is demonstrated. The measured average insertion loss is approximately 0.25 dB from 30 to 34 GHz. The measured output isolation in the same frequency band is greater than 15 dB.     

Design of Novel Compact Coupled Microstrip Power Divider With Harmonic Suppression

A new microstrip power divider (PD) is proposed which consists of a pair of parallel coupled-lines (PCLs) on a defected ground, and its two outputs are connected by a resistor and a capacitor. The even/odd-mode analysis shows that the defected ground structure (DGS) etched on the ground plane of PCL is equivalent to a strong parallel resonance circuit in the case of even-mode, and a weak inductance in the case of odd-mode. So, this kind of additional reactance effect is used intentionally to design compact coupled microstrip PD with harmonic suppression. Also, the phase-delay through the PD is discussed, which is different from conventional one. A 0.9 GHz PD is developed and experimental results verify it has low insertion loss, good impedance matching and isolation. Furthermore, the third harmonic suppression of this PD is better than ${-}35$ dB and the overall area of divider is only 34% of the conventional case.      

A Frequency Divider Implemented With a Subharmonic Mixer and a Divide-by-Two Divider

This letter proposes a divide-by-four injection-locked frequency divider (ILFD) with the use of a subharmonic mixer and a divide-by-two frequency divider (D2FD). The D2FD circuit consists of a two-stage differential CMOS ring oscillator with n-MOS switches directly coupled to its differential outputs, the measured phase noise of the D2FD is -97 dBc/Hz at 1-MHz offset from the free running frequency of 1.08GHz. The low-voltage CMOS divide-by-four FD (D4FD) has been implemented with the UMC 0.18-mum 1P6M CMOS technology and the power consumption is 9 mW at the supply voltage of 1.2 V. At the input power of 0 dBm, the D4FD can function properly with about 330-MHz locking range from 4.15 to 4.48GHz     

WiIkinson功分器改进和研究

随着通信技术的加速发展,传统的Wilkinson功分器已经无法满足多频及宽带的技术需求。基于ADS仿真设计软件,根据传统的功分器原理和结构,设计了一款谐振频率在900MHz附近的标准Wilkinson功分器。考虑到目前的实际需求,对其结构进行了适当调整和改进,从而仿真设计出了频率在900MHz附近的宽带Wilkinson功分器以及谐振频率为900MHz和2．OGHz的双频Wilkinson功分器,并且对其进行了良率分析,最终的仿真结果实现了预期的传输特性。     

A 10:1 Unequal Wilkinson Power Divider Using Coupled Lines With Two Shorts

A novel unequal Wilkinson power divider is presented. A coupled-line section with two shorts is proposed to realize the high characteristic impedance line, which cannot be implemented by conventional microstrip fabrication technique due to fabrication limitation. The proposed coupled-line structure is compatible with single layer integration and can be easily designed based on an even-odd mode analysis. As a design example, a 10:1 Wilkinson power divider at 2 GHz is fabricated and measured. The measured $-10~{rm dB}$ bandwidth of $S_{11}$ is about 16%, and the isolation $S_{32}$ is better than $-20~{rm dB}$ . The measured amplitude balance between output port 2 and port 3 is between $-10.20~{rm dB}$ and $-9.52~{rm dB}$, and the corresponding phase difference is between 0$^{circ}$ and 4.6$^{circ}$.      

A Variable-Ratio Microwave Power Divider and Multiplexer

A microwave circuit is presented which provides continuous variation of microwave power between two outputs in any desired ratio. A typical device utilizing the circuit is described, and other uses of the circuit are discussed. An X-band power divider was constructed which had a vswr of less than 1.2 at all times over the frequency range of 8.6 to 9.6 kmc, divided the total input energy between the outputs in any ratio from 1/10,000 to 1, and had less than 0.4-db total insertion loss. No other losses were present. Adjustment could be made under maximum power levels of the waveguide. Another use of the circuit is to couple two high-power transmitters into one output, thus providing a dual frequency antenna coupler or diplexer. By cascading diplexers, multiplexing can be accomplished.     

Ultra-Wideband Signal Impact on the Performances of IEEE 802.11b and Bluetooth Networks

This paper presents the results of a coexistence study investigating the impact of ultra-wideband (UWB) interference on IEEE 802.11b and Bluetooth networks. The results are based on the experimental test measurements made at the University of Oulu, Finland. Simple high-power UWB transmitters are used to interfere with victim networks. Preliminary results show that only under extreme interference conditions with thousands of equivalent Federal Communications Commission– (FCC)-compliant devices in close proximity, will the IEEE 802.11b and Bluetooth networks experience significant performance degradation. The impact of the UWB interference on the IEEE 802.11b network was insignificant if the distance to UWB transmitters was greater than 40 cm. The impact on Bluetooth was even less noticeable. In our study, several high-power UWB transmitters that greatly exceed the FCC radiation regulations have been used, and the measurement settings presents the worst case scenario because of the very short distance between the interferers and the victim system. Effectively our study approximates the use of thousands of FCC-complaint UWB devices in the same space.     

Optimum Design of a Wideband Two-Way Gysel Power Divider With Source to Load Impedance Matching

A two-way Gysel power divider is proposed as a modification of the common five-port Gysel divider, which has several advantages such as high power-handling capability and suitability for multi-staging to increase the frequency bandwidth. The even- and odd-mode technique is used to analyze its performance and the method of least squares is used to devise a procedure for its design and optimization. The source to load impedance matching is also incorporated into the design procedure and the input power is divided equally between the two outputs to provide an equal-split power divider. A method is proposed for the initial values of the widths and lengths of strips as an initial design of the two-way Gysel divider. The performance of the method of least squares design and optimization procedure is verified by the available simulation software packages and fabrication and measurements of two prototypes.     

宽带高隔离度功率分配器的设计

在固态毫米波功率放大器设计中,单片MMIC 输出功率较小,提高系统功率的有效方法是采用功率合成技术,目前的功率合成技术存在的设计难点是提高各分配支路间的隔离度。本文基于对传统魔T 的分析和改进,提出了一种高隔离度的3 dB 功率分配结构。经实验测试,运用该结构设计的功率分配器,在29.3-39.3GHz 的频带内两等分支路之间的隔离度可高达-42dB,两支路的不平衡度低于0.1dB,插入损耗优于-0.25dB,很好地满足了实际应用的要求。