TE111双模圆柱腔椭圆函数滤波器的耦合设计

滤波器是邻频频道合成器的关键部件之一,而耦合问题又是滤波器设计的关键.本文论述了TE111双模圆柱腔椭圆函数滤波器中应用的简并腔模及腔间与端面的耦合设计.文中巧妙地使用调谐螺钉和耦合螺钉,解决了双模圆柱腔椭圆函数滤波器中应用的简并腔模及腔间与端面的耦合设计问题,最后给出了该方法设计出的产品的实测数据.该产品使用效果好,用户满意.     

双槽型耦合腔行波管非线性注波互作用计算方法

建立了双槽型耦合腔行波管三维频域非线性注波互作用模型,推导出参与注波互作用电磁场及粒子运动方程组。根据模型与方程组编写非线性互作用计算程序,模拟注波互作用过程,得到输出功率、增益等性能参数。计算结果与X波段双槽型耦合腔行波管实测数据比较,以验证计算方法的准确性,并对互作用过程中的非线性现象进行分析,希望能够辅助行波管的设计。     

双模基片集成波导腔体的研究及其在带通滤波器中的应用

提出了基于双模谐振腔的基片集成波导带通滤波器的设计,用矩形腔体中的TE_(102)和TE_(201)模式来构建通带。在传统双模谐振器分析的基础上进行研究,利用加载在腔体中心的槽线来扰动简并模,单通带和双通带性能可以通过调节槽线的长度来进行转换,并给出了对以上的功能转换的解释和说明。设计了单通带和双通带两种基片集成波导滤波器,并进行了仿真和测试,测试结果和仿真结果有较好的吻合度。     

一种多模微带方形贴片带通滤波器的设计

提出了一种多模方式工作的微带方形贴片带通滤波器。通常设计微带方形贴片滤波器主要是利用TM1,0,0和TM0,1,0这一对简并主模实现单模或双模的工作方式。但是这些滤波器尚存一些有待完善的地方,诸如带内插损偏大,带宽受限等等。本文设计的带通滤波器不使用主模,而是利用三个高次模分量,通过一种简单的微扰方式和馈电方式激励起除简并主模以外的三个高次模分量,并使之相互耦合实现通带。仿真和测量结果充分说明,这种滤波器能够实现宽频段的通带响应,并且在通带内具有很低的插损和良好的阻抗匹配特性,能够广泛地适用于微波平面电路。     

分布损耗在耦合腔行波管中的应用技术

本文就分布损耗在休斯结构耦合腔行波管中的应用技术进行了综述,着重介绍了分布损耗在其慢波电路中的布局技术。用分布损耗涂层有选择地涂复耦合腔行波管的匹配腔片和主腔片,将能有效地抑制行波管振荡,获得行波管高稳定的工作。     

一种利用简并模的新型滤波器的研究

本文应用微扰理论研究了一种利用简并模的新型滤波器。对方形平面电路的边界给予小的微扰,则电路中TE_(010)和TE_(100)简并模的本征值被分离,受到微扰的方形乎面电路呈现出平坦的通带响应,而且通带内的插损很小。本文提供了这种滤波器的理论及实验的结果。     

基于菱形SIW的小型化双频可控带通滤波器

提出了一种四分之一模菱形基片集成波导谐振腔,设计并制作了一款小型化的双频带通滤波器.引入了T型槽线结构,实现了滤波器双通带中心频率的调节.利用间隙耦合、高低阶模式耦合和源负载耦合,在带外产生了7个传输零点,提高了滤波器的频率选择特性.滤波器双通带中心频率分别为4.4和7.7 GHz,3 dB带宽分别为517和405 M...     

交叉耦合介质谐振腔滤波器

论述了TE01模介质谐振腔滤波器的设计方法。主要分析了介质谐振腔的设计、谐振腔之间的耦合,包括电耦合与磁耦合的实现。为了使TE01模滤波器与其它高Q值的滤波器具有可比性,采用交叉耦合来实现高性能滤波特性。仿真设计了一个6阶准椭圆函数滤波器,4个传输零点对称的分布在通带两侧,实现了较好的带外抑制。最后设计了一个同轴腔与介质谐振器混合耦合的滤波器,用来抑制介质滤波器寄生通带的影响。     

耦合腔行波管功率合成

介绍了脉冲幅相一致耦合腔行波管的研制,并较为详细地介绍和分析了耦合腔行波管功率合成实验--脉冲相位一致性测试的一种途径.     

一维耦合腔行波管大信号计算

一维耦合腔行波管大信号计算张国兴，邓衡（东南大学）（南京电子管厂）－、介绍目前，耦合腔行波管的特性计算和工程设计所采用的Ｐｉｅｒｃｅ方法，对于大功率行波管不能给出令人满意的精度。随着耦合腔行波管输出功率越做越大，工作频宽要求越来越宽，以及相速渐变、跳...     

Band-notched ultra-wideband circular slot antenna with inverted c-shaped parasitic strip

A novel ultra-wideband (UWB) circular slot antenna with a parasitic strip for immunity at 5.2/5.8 GHz is proposed. The antenna has an indented circular stub and an inverted C-shaped parasitic strip embedded inside the circular slot. The desired band-notched UWB operation can be obtained by choosing the size of the inverted C-shaped parasitic strip. The proposed antenna has advantages of low cost, compact size and easy design. Details of the proposed design and experimental results of the constructed antennas are presented.     

Differentially slotted and differentially filled PIFAs

Based on a radiating and balanced mode decomposition it is shown that a planar inverted F antenna (PIFA) with a slot between the feed and shorting pins (differentially slotted PIFA) gives improved impedance control and a slightly wider bandwidth. The bandwidth can be further enhanced using a PIFA that is partially filled with conductor between the feed and shorting pins (differentially filled PIFA) and tuned with a capacitor.     

Bandwidth enhancement and size reduction of microstrip slot antennas

Reduced size microstrip monopole slot antennas with different slot shapes-straight, L and inverted T, and placed on a small ground plane, are investigated. The ground plane size is 50 mm/spl times/80 mm, which is about the size of a typical PC Wireless card. Detailed simulation and experimental investigations are conducted to understand their behavior and optimize for broadband operation. It is shown that, the variation in the slot shape, from straight to L and T shapes, helps in generating additional resonances, which when coupled to the original resonances of the slot, further increases impedance bandwidths. The bent shapes of the L and T slots reduce their height and provide more space on the ground plane for electronics. A mirror image dual L-slot antenna, placed at two adjacent corners of the ground plane, is also investigated and optimized for the polarization diversity. They provide an impedance bandwidth of 87%, with near orthogonal radiation characteristics. The measured impedance bandwidths (S/sub 11/=-10 dB) of up to 60%, 84%, and 80% are achieved for these straight, L and inverted T slots respectively, by suitably selecting their design parameters. The simulation results are in good agreement with the experimental data considering several practical issues.     

JTIDS 的时隙分配技术研究

JTIDS 采用 TDMA 的工作方式,时隙分配技术至关重要,讨论了该系统中的时隙结构、分配形式、分配方式和访问模式,指出了它与一般通信系统的区别,并提出了预分配和工作过程中按需分配相结合的时隙分配步骤。最后,介绍了一种同类系统 TIS 的主要特点。     

Ultra-Wideband Slot Antenna with Rejection of WLAN and ITU Bands Using Protruded Strip Resonators

In this paper, a different method for designing a new slot antenna with dual band-notched characteristic for ultra-wideband applications is presented. The proposed antenna consists of a square-ring radiating stub with an inverted T-shaped strip protruded inside the ring, a feed-line with an E-shaped strip protruded inside the rectangular slot, and a ground plane with a pair of L-shaped strips protruded inside the extra rectangular slot. In this study, by using a a pair of L-shaped strips protruded inside the slot in the ground plane, additional resonance is excited and hence much wider impedance bandwidth can be produced. By using this modified structure in the ground plane, the antenna provides a wide usable fractional bandwidth of more than 130 % (3.01–15.35 GHz). To generate a single band-notched function, we convert a square radiating patch to a square-ring with an inverted T-shaped strip. Finally, by adding a rectangular slot with a protruded E-shaped strip in the microstrip feed line, a dual band-notched function is achieved. The measured results reveal that the presented dual band-notched slot antenna offers a very wide bandwidth with two notched bands, covering all the 5–6 GHz wireless local area network, 8–8.5 GHz international telecommunication union bands.     

具有三阻带特性的新型平面超宽带天线研究

设计了一款具有三阻带特性的紧凑型超宽带天线。该天线采用共面波导结构进行馈电且能覆盖3.05~11.05 GHz的频率范围。通过在地表面加载两个对称的L形槽可以滤除WiMAX和卫星通信系统对超宽带系统的干扰,同时5.15~5.25 GHz和5.725~5.825 GHz的WLAN系统对超宽带系统的干扰分别被加载在辐射贴片上的倒C形和馈线上的倒U形槽滤除。天线经过设计,优化和制作,并对其进行了测试。测试结果表明,该天线尺寸为23mm×30 mm,其在3.05~11.05 GHz内VSWR小于2,并在3.30~4.16,5.0~5.4和5.6~6.0 GHz处形成了三个阻带。     

硅基槽型微环谐振器及其调谐特性研究

仿真和实验研究了含槽型(slot)光波导的反馈波导型微环谐振器的特性,将槽型光波导集成到Si基微环谐振器中,丰富Si基光波导的功能,为新型光电子器件的实现提供途径。通过锥形波导结构实现从传统波导到槽型波导的模式转换,减小传输损耗,采用时域有限差分法(FDTD)研究了光功率的分布和模式转换过程。结果显示,光功率逐渐转移到锥形结构两侧的槽型波导中并最终形成槽型波导中的传输模式,通过优化锥形结构能实现较高的模式转换效率,可以达到90%以上。采用电子束刻写技术和等离子刻蚀技术制备了反馈波导型槽型微环谐振器。实验显示,锥形波导能够实现模式的转换,光传输过程良好。通过在槽型波导中填充电光聚合物来改变槽型光波导的折射率,测量结果显示,传输谱谐振峰发生了明显移动,移动幅度达到5.6nm,器件具备很好的可调谐性。     

Hybrid Planar Inverted‐F Antenna with a T‐Shaped Slot on the Ground Plane

In this letter, a novel hybrid planar inverted‐F antenna (PIFA) with a T‐shaped slot on the ground plane is proposed. The loop structure formed by the feed line and shorting pin can be operated as a series and shunt inductance for the PIFA and the T‐shaped slot antenna, respectively. The PIFA operates at a frequency of 1.75 GHz, while the T‐shaped slot on the ground plane operates at 2.4 GHz by the same voltage feeding source. The height of the PIFA is 6.5 mm, and the size of an upper patch is designed to be 30 mm…16 mm. The measured relative impedance bandwidth of the PIFA and the T‐shaped slot are about 12% and 21%, respectively. In addition, good antenna performance was achieved.     

Higher order mode coupling effects in the feeding waveguide of a planar slot array

The effect of internal higher order modes in the feeding waveguide of a planar slot array is investigated. Both the centered-inclined coupling slot and the longitudinal-transverse coupling slot are considered. Method of moments solutions to pertinent coupled integral equations are investigated for arrays of coupling slots of the centered-inclined and longitudinal-transverse types between a main waveguide and crossed branch waveguides. It is demonstrated that, by including the TE/sub 20/ mode coupling in the analysis, most of the higher order mode effects can be accounted for in reduced height waveguides, whereas in waveguides of standard height there may be a small additional effect arising from the TE/sub 01/ mode coupling.<>     

开缝矩形腔屏蔽特性的研究

该文计算了在矩形腔上开有单缝时,缝长变化对所激励的屏蔽腔中最低模式的幅度和频率特性的影响。同时,采用时域-频域联合分析的方法,对屏蔽腔内观察点时域波形进行了分析,得到了不同频率分量在时域上的变化特性,以及缝长变化对它们的影响。