Microstrip Slotline Research Articles

Improved Design of Microstrip-to-Slotline Transition

A novel compact Ultra-Wide Band (UWB) microstrip-slotline transition utilizing high impedance chip resistor is proposed and analyzed. The reactance introduced by the microstrip open end and slotline short end, which is the main limitation to the bandwidth in the traditional structures, is minimized in the design. The model is analyzed with the method of equivalent circuits and simulated by the commercial software HFSS. To test the performance of this transition a back-to-back structure is fabricated. The measurement results show that the bandwidth of 45 octaves can be obtained while the insert loss is better than 0.7dB within the band.

Rectangular slotted microstrip line fed compact printed antenna with etched ground plane for UWB communications

Now a days, Microstrip or patch antennas are becoming increasingly useful because they can be printed directly onto a circuit board. Microstrip antennas are becoming very widespread within the mobile phone market. Patch antennas are low cost, have a low profile and are easily fabricated. And these antenna structures useful for wireless and mobile communications domain and also we can manufacture with low cost and suitable for handheld devices such as mobiles and Laptops. In this paper we have designed and proposed printed monopole antenna and also we have mentioned extensive simulation study and how we have utilized the usage of broadband techniques but also how we have achieved the huge bandwidth. We have used simple microstrip line for feeding the antennas and also these proposed antennas are well suitable for UWB frequency band from 3.1 to 10.6 GHz.

Compact dual‐notched balanced UWB BPF with folded triple‐mode slotline resonator

A compact dual-notched balanced ultra-wideband (UWB) bandpass filter (BPF) is designed by using the folded triple-mode slotline resonators and differential microstrip–slotline transitions. Two differential-mode transmission zeros near the passband edges are created to improve the selectivity, due to a cross-coupling between two microstrip open stubs beyond the cross-junction position as well as between the input and output. Good matching in the whole passband can be achieved by properly choosing the width of the microstrip open stubs. The inverse QWRs coupling stepped-impedance microstrip stub loaded in the 50 Ω microstrip feedlines can generate multiple transmission zeros to suppress the common-mode resonance and realise dual-notched bands in the UWB passband. Good agreement can be obtained between the measured results and simulated ones.

Investigation of Transformer Turns Ratio Between Feed and Slot of Aperture Coupled Slot Antenna by Using $S_{11}$ Parameter

This communication presents a simplified design approach to obtain the turns ratio nf which models the coupling between the microstrip feed and slot line of an aperture coupled slot antenna by using the S11 parameter. Equations are derived using S11 parameter to determine nf and simulations are carried out at 2 GHz using substrates of PCB FR4, Duroid 5870, and Duroid 6010. Results indicate nf is proportional to the slot length from 0 to 20 mm increasing rapidly with length. Over 20 mm slot length, the trend reduces and the value of nf tends towards 1. In addition, nf varies with the height of substrate but is little affected by dielectric constant of substrate which could therefore be ignored to simplify the design procedure. Measured results show good agreement with the theoretical model.

펄스 충실도 개선을 위한 UWB 안테나 설계기법 연구

본 논문에서는 임펄스 방사를 위한 UWB 안테나를 펄스 충실도 및 왜곡율 수식을 유도하고 적용하여 펄스 충실도가 개선된 안테나를 설계하는 방법에 대해 연구하였다. UWB 대역에서 지향성 특성을 갖는 안테나는 낮은 방사손실과, 임펄스 방사왜곡이 최소이어야 한다. 이를 위하여 광대역 임피던스 변환기와 마이크로스트립 슬롯라인 천이부 구조를 갖는 안테나 급전부를 설계하였다. 설계 및 제작된 UWB 안테나는 전파 무반사실에서 방사패턴을 측정하였다. 제작된 UWB 안테나의 임펄스 방사에의한 펄스충실도는 ±30° 빔폭내에서 93%이상의 개선된 결과를 얻었다.

Design and Development of a 2 × 1 Array of Slotted Microstrip Line Fed Shorted Patch Antenna for DCS Mobile Communication System

Compact microstrip antennas have recently received much attention due to the increasing demand of small antennas for personal communication equipment. The problem of achieving a wide impedance bandwidth for compact microstrip antennas is becoming an important topic in microstrip antenna design. In this paper the design and development of a 2 × 1 array of a low cost slotted microstrip line fed shorted patch antenna (MFSPA) has been presented. Both the shorted patch and microstrip line feed network have air substrate. The material cost is thus reduced to a minimum. The array consists of two adjacent patches fed, using a simple microstrip T network. The impedance bandwidth of nearly 40%, covering the bandwidth requirement of 1750 MHz band is obtained. Also the antenna exhibits dual band operation. The cross polarization radiation in H-Plane observed with a single element antenna has been reduced considerably with 2 × 1 array. A peak antenna gain of 9.2 dBi is obtained with a small variation of 0.8 dBi. From the results obtained it is clear that the antenna array studied has a low cost fabrication and is suitable for applications in DCS mobile communication base station.

최적 임펄스 전송을 위한 초광대역 테이퍼 슬롯 안테나 설계

본 논문에서는 UWB 대역에서 최적 임펄스 신호 전송을 위한 테이퍼 슬롯 안테나(Tapered Slot Antenna: TSA) 설계에 대해 연구하였다. UWB 대역에서 동작하는 TSA는 end-fire 특성을 갖는 광대역 안테나로, 펄스 전송을 위한 IR-UWB(Impulse Radio Ultra-Wide Band) 시스템에 적합하다. 지향성 특성을 갖는 테이퍼 슬롯 안테나는 UWB 대역에서 손실이 적고, 임펄스 전송시 최소 에러를 가져야 한다. 전송되는 펄스 왜곡을 최소로 하기 위해 테이퍼 슬롯 안테나 급전부를 구성하는 광대역 임피던스 변환기와 microstrip/slotline 천이부 설계에 대해 연구하였으며, 설계된 테이퍼 슬롯 안테나에 대한 펄스 충실도는 전자기파에 대한 시간 영역 분석이 가능한 CST를 이용한 FDTD(Finite-Difference Time-Domain) 시뮬레이션과 펄스 상관식 유도를 통해 계산하였으며, 제작된 안테나에 대해 두 안테나를 0.5 미터 이격시킨 두 안테나 사이에서 약 93.89 % 정도의 양호한 결과를 얻을 수 있었다. 또한 chirp Z-변환 알고리즘을 유도를 통해, 나노초 이하의 펄스 신호에 대해 zoom-in 기능을 부여함으로써 펄스 신호에 대한 왜곡, 지연 및 분산 특성 등의 분석이 가능하다. This paper presents a tapered slot-antenna(TSA) for optimal impulse-signal transmission in ultra-wide band(UWB). The proposed TSA provides radiates in end-fire direction, which meets an impulse-radio UWB(IR-UWB) system demands(e.g., low loss, thus less error throughout the UWB band). In order to minimize the pulse distortion, we used an wideband impedance transformer and a microstrip slotline. The pulse fidelity characteristics was evaluated with finite-difference time-domain(FDTD) analysis technique and pulse fidelity correlation equation. Approximately 93.89 % pulse fidelity was obtained between the two antennas in 0.5 m range. Additionally, derived chirp Z-transform algorithm enables us to utilize the zoom-in option on the pulse signal in few nano-seconds below. Thus, it is possible to analyze the pulse signal distortion, delay or dispersion characteristics.

Microstrip‐CPW bandpass filter for antenna application

AbstractThis article presents a quasi‐lumped bandpass filter with CPW‐microstrip ports. The structure serves as CPW‐microstrip transmission in addition to its filtering function. The filter was integrated with a microstrip patch antenna. To enable the filter design, the characteristic impedance of the slotted microstrip line and the coupling strength of microstrip to microstrip, CPW to CPW and microstrip to CPW transitions were calculated. © 2007 Wiley Periodicals, Inc. Microwave Opt Technol Lett 50: 51–55, 2008; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/mop.23001

Analysis of Open Microstrip and Slot Lines with Semiconductor Substrates

The numerical study of open microstrip lines (MSLs) and slot lines (SLs) with n -Si substrates. Two methods of singular integral equations (SIE) were used in our calculations. The first method we used for solving a problem was based on TEM-approximation and the second method was electrodynamically rigorous. The algorithms that we applied in our computations allowed us to take into account the finite substrate width and the finite metal strip thickness. The electrodynamical characteristics of MSLs on the specific resistivity of the substrate material, the metal strip width, the distance between the metal strip and the substrate lateral edges were investigated in this article. Also the dispersion dependences were determined for the main and higher modes of a noncoplanar SL and coplanar SLs. We presented characteristics of open MSLs and SLs having different crosssections to show the algorithm efficiency. The calculated and measured results agreed when compared to one another.

Ultra-wideband tapered slot antenna with band cutoff characteristic

A novel ultra-wideband (UWB) tapered slot antenna (TSA) is proposed that has both enhanced impedance bandwidth enough to cover UWB systems and band cutoff characteristic of 5 GHz WLAN band limited by IEEE802.11a and HIPERLAN/2. To achieve these two characteristics of wide bandwidth and partial band cutoff at the TSA, a broadband microstrip–slotline transition with multi-arm stubs and λ/4 short stubs, respectively, is used. From measured results, it is observed that wide bandwidth of about 2 octaves from 2.8 to 11.09 GHz for the VSWR<2 is achieved, while 5.05–5.93 GHz is cutoff with the radiated power of this cutoff band effectively suppressed as about −9 dB for the peak power level of other bands.

Analysis of the propagation of leaky magnetostatic modes in normally magnetized microstrip and slot lines

The propagation of leaky forward magnetostatic (MS) volume waves along ferrite-loaded microstrip and slot lines is analyzed. This phenomenon is studied by means of a numerical approach based on the residue calculus technique because of its good numerical convergence and stability. The proposed method allows for a quick and accurate computation of the phase and attenuation constants of the leaky MS modes. A comparative analysis between both microstrip lines and slot lines is carried out, and some new physical effects, such as MS resonances in the radiation loss, are reported. The advantages of the proposed method of analysis over other numerical methods, such as Galerkin's or moment methods, are also discussed.

Theoretical and experimental investigations on rectangular dielectric resonator antennas

Theoretical and experimental investigations on rectangular dielectric resonator antennas having a value of /spl epsiv//sub r/, in the range of 10 to 100 are reported. The resonant frequencies and radiation Q-factors of the lowest order "magnetic-dipole" modes are derived on the basis of a first-order theory. The accuracy of the model in predicting the resonant frequency and radiation Q-factor is verified by comparison with results of a rigorous theory and experiments. Various feeds for the antennas such as probe, microstrip slot, and microstrip line are described. Measured radiation patterns are shown and the effect of feed and mode degeneracy on the cross-polarisation levels is discussed.

Review of printed Marchand and double Y baluns: characteristics and application

A review of printed baluns is presented. This is divided into two main groups; Marchand baluns (band pass networks) and double Y baluns (all pass networks). For each of these groups of baluns, three different realizations are given: microstrip-slot line, CPW-slot line and CPW/sub FGP/-CPS and their theoretical and experimental characteristics are compared. Simple expressions for the design of Marchand baluns with Chebyshev response, which replace the complicated synthesis proposed by Cloete are derived. Superior broadbandwidth features of double Y baluns are demonstrated in the design of two uniplanar double balanced mixers. Both the double Y mixer and the CPW/sub FGP/-CPS mixer have a frequency bandwidth 1:6, whilst maintaining other performance similar to that achieved with classical double balanced mixers. >

Optical control of wave propagation in microstrip-slot lines at d band

The dispersion relationships for microstrip-slot lines are analysed by the spectral domain method and evaluated numerically as a function of plasma density for an optically induced plasma. The frequency range considered corresponds to the W and D band range, and the microstrip is realised on high-resistivity silicon. The experimental work was undertaken at frequencies ranging from 90 to 170 GHz using 5 kΩ cm silicon substrates with different strip widths irradiated by light emitting diodes radiating at a wavelength of 820 nm. Optical control was confirmed by measuring the change in propagation loss resulting from the illumination. A wave attenuation of 10 dB was determined for a line of length of 30 mm, and a plasma relaxation time of 120 μs was measured at 137 GHz. Applications of this line are briefly discussed.

Analysis and design of microstrip-slot line for phase shifting applications

The analysis and design of printed phase shifters based on the microstrip line are described. A spectral-domain analysis is presented where the necessary Green's functions are formulated using the transmission matrix technique. The nonreciprocal characteristics for single-layer and multilayer structures are studied. Microstrip-slot in a multilayer structure of ferrite and high-dielectric material is found to have considerably more nonreciprocity than microstrip-slot for microstrip in a single-layer structure. Over 65 degrees /cm is predicted for certain optimized designs. This, in addition to the 50- Omega design capability of the line, makes the microstrip-slot line a suitable choice for phase shifting applications. A multilayer microstrip-slot line was constructed on a rectangular ferrite toroid. Differential phase shifts of roughly 45 degrees /cm were measured over a 6.0-8.5-GHz frequency range. These results are in good agreement with the analysis.< <ETX xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">&gt;</ETX>

Transient Analysis of a Directional Coupler Using a Coupled Mlcrostrip Slot Line in Three-Dimensional Space (Short Paper)

In recent MIC techniques, double-sided MIC has been studied because its advantages in propagation characteristics are greater than that conventional MIC's. A coupled microstrip slotline is one of them. Its application to various circuit elements has often been discussed. But the coupled microstrip slotline is essentially three-dimensional structure, so the analysis demands a rigorous three-dimensional treatment. Also, the recent high-speed pulse technique demands analysis in the time domain. The present paper treats a directional coupler using the coupled microstrip slotline in three-dimensional space and time. The results of the directional coupler analysis is presented with the complicated time variation of the three-dimensional electromagnetic field. So, the mechanism of the directional coupling phenomena that is produced by the propagation characteristics of the even and odd modes is presented in the time domain, In particular, the instantaneous diagram of the Poynting vector details the energy flow in the transient process. For the analysis of the characteristics of the complex microwave device, these results present the utilities of the various field distributions that are obtained by the three-dimensional vector analysis in the time domain.

Analysis of microstrip-slotline ring 3 dB directional couplers

The paper deals with the analysis of a new class of microstrip slotline ring 3 dB directional couplers which possess topological symmetry with respect to two of the input ports. Slotline or slotline microstrip T-junctions are used to obtain the frequency independent 180° phase shift. This provides for a high frequency independent isolation between the input ports. In the analysis effects of microstrip T-junctions and impedance transformation in the microstrip slotline transitions have been taken into account. The numerical results obtained predict that couplers operating over 30–50% bandwidth are feasible. Some additional design flexibility resulting from the coupler impedance transformation properties has also been demonstrated.

New MIC Power Dividers Using Coupled Microstrip-Slot Lines: Two-Sided MIC Power Dividers

New microwave integrated circuit (MIC) power dividers have been proposed. These power dividers utilize both substrate surfaces and employ coupled microstrip-slot lines, microstrip lines, and slotlines; therefore, we make use of the two-sided MIC technique. The out-of-phase-type power dividers, as well as the in-phase-type circuits, can be constructed by the circuit configuration method described in this paper. Coupled microstrip slot lines, an important component of the power dividers, have been analyzed by the spectral-domain method, and their characteristics have been calculated and the numerical results shown for several different structural parameters for the purpose of designing power dividers. The out-of-phase-type power divider was fabricated at the 26-GHz band and good performance achieved, confirming the calculated accuracy through experimental results. The new two-sided MIC power dividers are expected to have wide applications at the millimeter-wave band.

Integrated Balanced BPSK and QPSK Modulators for the Ka-Band

Microwave integrated circuit (MIC) balanced biphase-shift-keying (BPSK) and quadri-phase-shift-keying (QPSK) modulators have been achieved in the 27-GHz band. The modulators are fabricated using a combination of microstrip lines and slot lines, viz., tow-sided MIC. The diodes used are beam-lean Schottky-barrier diodes. Balanced BPSK modulation is performed by path-switching and mode transformation from the slot line to microstrip lines. The insertion loss is 2.2 dB at a carrier frequency of 27 GHz. The phase error and the amplitude deviation are less than 1° and 0.5 dB, respectively. The QPSK modulator consists of two BPSK modulators, a power divider, and a branch-line hybrid coupler. The configuration of the modulator is the parallel-connected type. The insertion loss is 6.3 dB at a carrier frequency of 27 GHz. The phase error is less than 2°, and the rise time and fall time of the modulated earner are less than 300 ps. The isolation between the carrier input port and the QPSK modulated earner output port is greater than 25 dB. These modulators can be extended to the millimeter-wave band.

The Effect of Neighboring Conductors on the Currents and Fields in Plane Parallel Transmission Lines

In this paper the current distribution is calculated for a microstrip line in the presence of a neighboring strip. The electric field is calculated and the characteristic impedance of the slotted microstrip line is determined. A graph of characteristic impedance is given for odd and even excitations. The calculations are carried out by setting up a singular integral equation which is solved using a finite integral transform. This method has the advantage that the calculations can be generalized in a straightforward manner for the multislotted line.