Compact cross-coupled circular cavity filters using multilayer substrate integrated waveguide

Using standard low-temperature co-fired ceramic technology, a novel fourth-order cross-coupled circular cavity filter is proposed, where multilayer substrate integrated waveguides are implemented. In particular, one slot is introduced on the metal surface of one filter, which can suppress the spurious mode in the filter cavities effectively. Good agreement is obtained between the simulated and measured S-parameters of the proposed new structure.     

Development of a low cost microwave mixer using a broad-band substrate integrated waveguide (SIW) coupler

A low cost single-balanced mixer is designed using a newly designed 90/spl deg/ substrate integrated waveguide (SIW) 3-dB coupler, which takes the advantages of low cost, low profile, and high performance. An X-band single-balanced SIW mixer is designed and fabricated with a standard printed circuit board process. Measured conversion loss of 6.8dB and the wide-band response from 8.5 to 12GHz are presented.     

High isolation sub-harmonic up-converter using substrate integrated waveguide

A low cost high isolation sub-harmonic microwave up-converter is designed using a substrate integrated waveguide (SIW). By employing the cutoff mode concept of SIW, the up-converter has effectively suppressed the output components of local oscillator (LO) frequency and image frequency. Experimental results show an additional 50 dB isolation is achieved with the SIW.     

Novel half-mode substrate integrated waveguide bandpass filters using semi-hexagonal resonators

In this paper, a novel bandpass filter is presented, designed, and implemented by using a triple mode semi-hexagonal Half-Mode Substrate Integrated Waveguide (HMSIW) cavity, which has the advantages of compact size, low insertion loss, and high selectivity in upper and lower passband. To realize a triple mode filter, the first resonant mode is shifted to near the next two modes using a via hole perturbation. Two microstrip open stubs connected to open edge of HMSIW resonator are introduced to generate two transmission zeros in the lower passband. The position of transmission zeros could be controlled by adjusting the coupling gap between the microstrip open stub resonators. By etching an E-shape slot on the top plate of HMSIW resonator, two other transmission zeros are produced in the upper passband. A wide-band planar six-pole bandpass filter, which has the advantages of wide bandwidth and small size, is also proposed and fabricated by cascading two triple mode resonators. Measured results indicate that 29% and 47% fractional bandwidth, as well as approximately 1 dB and 1.1 dB insertion loss, are achieved for the proposed filters. Measured results of all those filters agree well with the simulated results.     

W-band substrate integrated waveguide slot antenna

A W-band substrate integrated waveguide slot antenna has been designed and tested. The antenna has been realised using a reduced height waveguide in photoimageable thick film technology. Experimental and simulated return loss and radiation pattern measurements are presented.     

Broadband transition between air-filled waveguide and substrate integrated waveguide

A Ka-band broadband transition between an air-filled waveguide and a substrate integrated waveguide (SIW) is proposed. The transition is realised by using a radial probe inserted into the height-tapered metal waveguide. Results show that an insertion loss less than 2.5 dB and a return loss better than 14 dB in the frequency band 28.3-39.5 GHz are obtained for a back-to-back structure     

Low phase-noise integrated voltage controlled oscillator design using LTCC technology

This paper describes the design and implementation of a highly integrated voltage controlled oscillator (VCO) module based upon Low-Temperature Co-fired Ceramic (LTCC) packaging technology. The circuit is realized by embedding the strip-line resonator and lumped passives inside a multilayer LTCC substrate. Measurement results of a silicon bipolar VCO circuit operating at 2.4 GHz is shown. The constructed module is compact in size and has good phase noise performance.     

Broadband substrate integrated waveguide to rectangular waveguide transition with fin-line

A novel broadband transition from a substrate integrated waveguide to a rectangle waveguide with an antipodal fin-line in its quasi-TE mode is presented. Impedance match and field mode gradual changing of transition circuits have been carefully analysed and performed. Experimental results show about a 1.6 dB insertion loss and greater than 12 dB return loss for back-to-back transitions over 10 GHz bandwidth from 26.5 to 40 GHz, so single transition insertion loss is about 0.8 dB. The transition is proposed for low-loss front-end circuits in the millimetre-wave band.     

A substrate integrated waveguide degree-2 circulator

A substrate integrated waveguide (SIW) circulator is proposed and demonstrated in this work that can facilitate the integration of planar active components with high-Q passive components. Very satisfactory experimental and theoretical results are provided, at 22 GHz, for a degree-2 junction circulator using a post resonator. It also includes experimental results on the classic gyrator circuit of this type of junction.     

基片集成脊波导传输特性的研究

将构成基片集成脊波导脊的一排金属针等效成实金属脊。基于基片集成波导等效宽度计算公式推导了基片集成脊波导等效脊宽的计算公式。运用横向谐振法推导了TE_m0模基片集成脊波导截止频率的计算公式,同时运用这些公式分别计算了TE₁₀模、TE₂₀模和TE₃₀模基片集成脊波导的截止频率,并与仿真软件计算的结果和参考文献所给结果进行了比较。结果显示:利用所给公式计算的结果具有较高的精度,且使用方便。此外,还研究了截止频率与脊宽和脊隙之间的关系,对一种适合宽带应用的宽脊结构进行了讨论。     

Multimode substrate integrated waveguide H-plane monopulse feed

A structure for an optimum monopulse feed is proposed at Ku-band using a muftimode substrate integrated waveguide (SIW). A 180deg directional coupler is employed to realise the in- or out-of-phase feeding mechanism, and an H-plane moder is used to generate the odd and even illumination laws at the aperture. A horn antenna is constructed from the dielectric substrate and three other copper plates to radiate energy effectively. All parts have been fabricated in a normal PCB process. Good agreement between the simulation and measurement is observed, which certifies that this type of SIW monopulse feed is feasible and has good characteristics.     

Dispersion characteristics of substrate integrated rectangular waveguide

Dispersion properties of the substrate integrated rectangular waveguide (SIRW) are rigorously obtained using the BI-RME method combined with the Floquet's theorem. Our analysis shows that the SIRW basically has the same guided-wave characteristics as the conventional rectangular waveguide. Empirical equations are derived from the calculated dispersion curves in order to estimate the cutoff frequency of the first two dominant modes of the SIRW To validate the analysis results, an SIRW guide was designed and measured. Very good agreements between the experimental and theoretical results were obtained.     

Broadband transition between half mode substrate integrated waveguide and rectangular waveguide

A broadband transition between a half mode substrate integrated waveguide and a rectangular waveguide with an antipodal fin-line in its quasi-TEM mode is presented. Experimental results show about 1.3 dB insertion loss and below 215 dB return loss for a back-toback double transition over 10 GHz bandwidth from 26.5 to 40 GHz (the single transition insertion loss is about 0.65 dB). The transition may be used in low-loss and low-noise front-end circuits of the microwave and millimetre-wave bands.     

基于基片集成波导技术的超宽带八木天线

为便于系统集成和简化馈电电路,利用基片集成波导技术设计新型八木天线.通过引向器异面分置来提高增益,提出了X波段基片集成波导八木天线,并分析了引向器个数对天线增益和工作带宽的影响.利用增加激励器个数和改变馈电结构来扩展带宽,设计了单模和半模基片集成波导双激励超宽带八木天线,仿真和测试结果表明,基片集成波导双激励八木天线的工作带宽超过40％,带内增益均高于7.0 dBi,中心频率处为9.0dBi,可以广泛应用于雷达和通信系统中.     

一种基于介质集成波导腔的小型化滤波器

为了实现介质集成波导滤波器的进一步小型化,通常要改进其谐振腔;通过在传统的介质集成波导谐振腔中心位置插入一个短路销钉,并且将其上金属平面与腔体四周的金属壁绝缘可以实现其体积的小型化.采用这种小型化谐振腔,设计了四腔微带滤波器,工作在2.8 GHz,相对带宽14.3％.最终加工了这个原型滤波器,仿真和测试结果吻合良好.相比采用传统的介质集成波导谐振腔的滤波器,这个滤波器尺寸可以减小到其1/4以下.     

Self-equalised pseudo-elliptical filter made of substrate integrated waveguide

A self-equalised pseudo-elliptical filter on the basis of substrate integrated waveguide technology is proposed and demonstrated over the Ka-band range. The extracted-pole technique is used to synthesise a sixth-order filter with non-resonating nodes. Measured results of the filter exhibit a high selectivity and a minimum in-band insertion loss of about 2.0 dB and small inband group delay variation.     

Guided-wave and leakage characteristics of substrate integrated waveguide

The substrate integrated waveguide (SIW) technique makes it possible that a complete circuit including planar circuitry, transitions, and rectangular waveguides are fabricated in planar form using a standard printed circuit board or other planar processing techniques. In this paper, guided wave and modes characteristics of such an SIW periodic structure are studied in detail for the first time. A numerical multimode calibration procedure is proposed and developed with a commercial software package on the basis of a full-wave finite-element method for the accurate extraction of complex propagation constants of the SIW structure. Two different lengths of the SIW are numerically simulated under multimode excitation. By means of our proposed technique, the complex propagation constant of each SIW mode can accurately be extracted and the electromagnetic bandstop phenomena of periodic structures are also investigated. Experiments are made to validate our proposed technique. Simple design rules are provided and discussed.     

Reduction of dielectric losses in substrate integrated waveguide

The impact of different loss mechanisms on the attenuation of the substrate integrated waveguide (SIW) is investigated. Using a multilayer PCB technology, an air-cut region is introduced in the SIW structure to reduce the attenuation caused by dielectric losses. Numerical results obtained using a mode-matching technique verify that the attenuation constant of the SIW can be reduced significantly if the width of the air-cut is chosen properly     

Chip-package codesign of integrated voltage-controlled oscillator in LCP substrate

This paper presents the design and characterization of a negative resistance type 1.9-GHz oscillator using high quality factor (Q) embedded lumped-element LC passives in an organic-based substrate with liquid crystalline polymer (LCP) dielectric material. A design strategy using analytical models is implemented to determine the value of the base inductance subject to the constraints set by power dissipation. Additionally, the effect of component Qs on the phase noise is qualitatively discussed. This paper also addresses the effects of the parasitics of the surface-mount active devices on the noise spectrum of a negative resistance type voltage-controlled oscillator (VCO). The designed VCO is fully embedded in the LCP substrate and uses high Q on-package passive components. The VCO was measured to operate at 1.92 GHz dissipating 14 mW of dc power and measured a phase noise of -118dBc/Hz and -133 dBc/Hz at 600 KHz and 3-MHz offset, respectively. The high Q of the LC tank circuit was utilized to optimize the VCO to operate from a 2-V supply at bias current of 0.9 mA. Finally, the design and implementation issues in a 2.25-GHz Colpitt's oscillator on LCP substrate are shown. The effects of scaling capacitance ratio on VCO phase noise and on power consumption are verified for the Colpitt's oscillator.