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1.
A complete UMTS transmitter is proposed. It is composed of a radiofrequency (RF) signal generator, a power stage, and a bulk acoustic wave (BAW) duplexer. The 90‐nm CMOS digital RF signal generator is based on a third‐order delta‐sigma modulator using innovative design techniques to increase work frequency and a BAW filter to get rid of out‐of‐band quantization noise. The filter exhibits very high rejection, 3 dB of insertion losses at 1.95 GHz for a 3% fractional bandwidth. The 0.25‐μm BiCMOS power stage feeds a BAW duplexer that allows to share a common between W‐CDMA emission and reception. This 4 × 4 mm2 duplexer, built with flip‐chipped BAW on glass substrate, ensures good isolation. The full transmitter measurements show the compliance with respect to spurious emissions in the different frequency bands and an EVM measurement at the state of the art (<5%). © 2011 Wiley Periodicals, Inc. Int J RF and Microwave CAE, 2011.  相似文献   

2.
This article presents a study of ladder‐lattice bulk acoustic wave (BAW) filters. First, a review of BAW technology and filters topologies is addressed. Next, a mixed ladder‐lattice BAW filter for application on W‐CDMA reception front‐ends (2.11–2.17 GHz) is presented. An improved solidly mounted resonators (SMR) technology was used for the filter implementation. The filter synthesis methodology is briefly described. Layout guidelines are discussed enabling an optimized filter design. The filter on‐wafer measurement results are as follows: ?3.55 dB of insertion loss, ?8.7 dB of return loss, an isolation higher than ?47 dB at the transmission band (1.92–1.98 GHz) and an improved selectivity (?30 dB at 2.14 GHz ± 60 MHz). Therefore, we can observe that the mixed topology combines the advantages of ladder and lattice networks, having very steep responses and an improved isolation at undesired bands. © 2008 Wiley Periodicals, Inc. Int J RF and Microwave CAE, 2008.  相似文献   

3.
This paper presents the impedance behavior of the bulk acoustic wave solidly mounted resonators (BAW‐SMR). Also, it shows the effects of the addition of passive elements (L, C) to this type of resonators. In addition, this article presents a tunable BAW‐SMR filter realized in a ladder topology used for the 802.11b/g standard (2.40–2.48 GHz). Mainly, the filter fulfills the requirements for the WLAN 802.11 b/g standard, presenting a measured ?3.3 dB of insertion loss, –12.7 dB of return loss and selectivity higher than 33 dB at ±30 MHz of the bandwidth. This tunable BAW‐SMR filter has reduced dimensions (1035 × 1075 μm2). Moreover, we show how to shift the center frequency of this tunable filter toward higher and lower frequencies by adding passive elements. Measured shifts of ?1.3% of the center frequency (2.44 GHz) toward lower frequency and +0.6% of the center frequency toward higher frequencies are obtained. © 2011 Wiley Periodicals, Inc. Int J RF and Microwave CAE, 2011.  相似文献   

4.
章安良 《计算机仿真》2008,25(3):199-202
传统的复杂声表面波滤波器设计方法繁杂,迫切需要简炼的复杂声表面波滤波器设计技术,提出了一种新的声表面波滤波器设计方法,它将变迹的输入和输出叉指换能器进行"分割-求和",以声表面波滤波器中心频率处的插入损耗和旁瓣抑制作为寻优目标,叉指换能器的指条长度作为基因,通过选择、交叉和变异等遗传操作,自动生成复杂声表面波滤波器的输入和输出叉指换能器所有指条长度,进化实例表明,所提出的设计方法能自动、高效地满足所要求设计指标的复杂声表面波滤波器,且具有较强的实用价值.  相似文献   

5.
Bulk‐acoustic‐wave‐coupled resonator filters is an emerging technology that is capable of meeting increasingly ambitious demands of wireless applications by addressing performance, chip size, and die cost. This article outlines the fundamental design principles of these filters. A major consideration of filter design is the choice of the coupling structure between the two vertically stacked resonators. This can be either a multilayer Bragg coupler or a novel structure using a single layer of a very low acoustic impedance material. It is demonstrated how spurious modes are related to the dispersion diagram and how they affect the passband characteristics. For the suppression of these spurious modes suitable edge termination techniques are discussed. Based on optimized coupler performance and known parasitic effects, we analyze circuit design methods for microwave filters and duplexers with specific passband, roll‐off, and wideband responses. We show as example a miniature 2.0 × 1.6 mm2 Universal Mobile Telecommunication System (UMTS) Band1 duplexer fabricated using the coupler resonator technology. © 2011 Wiley Periodicals, Inc. Int J RF and Microwave CAE, 2011.  相似文献   

6.
A large body of literature exists on the filter design problem, assuming that the system to be filtered is known. However, in most practical situations, the system is not known, but a set of measured data is available. In such situations, a two‐step procedure is typically adopted: a model is identified from this data set, and a filter is designed based on the identified model. In this paper, we consider an alternative approach, which uses the available data not for the identification of a model, but for the direct design of the filter. Such a direct design is investigated within a parametric‐statistical framework for both the cases of linear time‐invariant and nonlinear systems. The noise is assumed to be stochastic, and optimality refers to minimizing the estimation error variance. It is shown that the direct design has superior features with respect to the two‐step design, especially in the presence of modeling errors. Another relevant advantage of the direct design over the two‐step procedure is that minimum variance (Kalman) filters for nonlinear systems are, in general, difficult to derive and/or to implement. On the contrary, the direct approach allows for a very efficient filter design. To demonstrate the effectiveness of the proposed direct design, two examples are presented: the first is related to estimation of the Lorentz chaotic attractor; the second, involving real data, is related to estimation of vehicle yaw rate. Copyright © 2011 John Wiley & Sons, Ltd.  相似文献   

7.
An innovative technique of neural network optimization of substantially less computational cost is presented as a procedure suitable for viable computer‐aided design of complex microwave systems. The number of necessary full‐wave simulations in this optimization procedure is dramatically reduced because of a special objective function (OF) and constrained optimization response surface (CORS) sampling in the dynamic training of the decomposed radial‐basis‐function network. A high rate of convergence to an optimization objective is shown to be dependent on the combined effect of the OF and CORS technique. Performance of the algorithm is illustrated by its application to a waveguide band‐pass filter, a loaded microwave oven, and a dielectric resonator antenna; their optimal designs are found from five‐parameter optimizations requiring as little as 167, 177, and 99 analyses, respectively. © 2011 Wiley Periodicals, Inc. Int J RF and Microwave CAE, 2011.  相似文献   

8.
针对体声波(BAW)滤波器布局中芯片面积利用率低、设计周期长、制造成本高等问题,提出了一种基于改进人工蜂群算法的BAW滤波器自动布局方法。首先构建了自动布局的评价模型,通过结合利用圆形容器的顺序布局和基于旋转角度编码的聚拢布局来简化自动布局的难度;同时采用了一种改进人工蜂群算法去搜寻BAW滤波器的最优顺序布局和聚拢布局方案;最后,结合多组BAW滤波器的设计案例验证自动布局算法的有效性,其布局有效面积占比提升约17%,整体布局呈方形,且完成滤波器的自动布局仅需30 min。结果表明在保证BAW滤波器性能的前提下,算法可有效提升芯片面积利用率、大幅缩减滤波器的设计周期。  相似文献   

9.
A novel delay‐dependent filtering design approach is developed for a class of linear piecewise discrete‐time systems with convex‐bounded parametric uncertainties and time‐varying delays. The time‐delays appear in the state as well as the output and measurement channels. The filter has a linear full‐order structure and guarantees the desired estimation accuracy over the entire uncertainty polytope. The desired accuracy is assessed in terms of either ??‐performance or ??2–?? criteria. A new parametrization procedure based on a combined Finsler's Lemma and piecewise Lyapunov–Krasovskii functional is established to yield sufficient conditions for delay‐dependent filter feasibility. The filter gains are determined by solving a convex optimization problem over linear matrix inequalities. In comparison to the existing design methods, the developed methodology yields the least conservative measures since all previous overdesign limitations are almost eliminated. By means of simulation examples, the advantages of the developed technique are readily demonstrated. Copyright © 2009 John Wiley & Sons, Ltd.  相似文献   

10.
We consider the design of transfer functions (filters) satisfying upper and lower bounds on the frequency response magnitude or on phase response, in the continuous and discrete time domains. The paper contribution is to prove that such problems are equivalent to finite dimensional convex optimization problems involving linear matrix inequality constraints. At now, such optimization problems can be efficiently solved. Note that this filter design problem is usually reduced to a semi infinite dimensional linear programming optimization problem under the additional assumption that the filter poles are fixed (for instance, when considering FIR design). Furthermore, the semi infinite dimensional optimization is practically solved, using a gridding approach on the frequency. In addition to be finite dimensional, our formulation allows to set or not the filter poles. These problems were mainly considered in signal processing. Our interest is to propose an approach dedicated to automatic control problems. In this paper, we focus on the following problems: design of weighting transfers for H control and design of lead‐lag networks for control. Numerical applications emphasize the interest of the proposed results. Copyright © 2003 John Wiley & Sons, Ltd.  相似文献   

11.
In this article, a double‐T‐shaped stub centrally loaded uniform impedance resonator (UIR) is introduced and its resonant characteristics are well clarified, which provided a simple approach for triple‐mode wideband bandpass filter (BPF) design. The double‐T‐shaped stub consists of a T‐shaped stub at the center of UIR and two shunt uniform‐impedance stubs at the T‐shaped stub. Furthermore, loading technique for zero‐voltage point is employed to guide design procedure from UIR to the proposed resonator. The resonant frequencies of the first three modes for the resonator can be free to adjust by the length of the UIR and the two kinds of stub. Finally, a compact wideband BPF is designed, fabricated, and measured. The measured results are in good agreement with the full‐wave simulation results. The realized wideband filter exhibits a 3 dB fractional bandwidth of 69.1% with good in‐band filtering performance, wide stopband, and sharp out‐of‐band rejection skirt.  相似文献   

12.
A novel and very small metamaterial notch filter below 900 MHz is proposed in this paper. In the UHF band, compared to the size of the open‐ended quarter‐wavelength stub that is, 0.25 λg (42 mm), the length of the proposed filter is 0.07 λg (12 mm) approximately five times smaller. The notch filter is realized by a very short 90°‐phase shifter of the CRLH structure with one‐end open‐terminated. The design method is explained theoretically, while the circuit and geometry are simulated and validated through EM simulations and fabrication. The measured results show a high degree of agreement with the simulated results. The results illustrate the notch created at 900 MHz by the filter to avoid the conflict with Z‐wave communication, UHF RFID tag and uplink of GSM‐E. © 2016 Wiley Periodicals, Inc. Int J RF and Microwave CAE 26:247–253, 2016.  相似文献   

13.
This work presents an efficient method for the design of substrate integrated waveguide (SIW) filters. The proposed design approach is based on a combined use of equivalent circuit model of a filter and a space mapping technique. A reduced number of full‐wave evaluations are needed, leading to a reduced optimization time. A novel SIW filter with improved stop‐band characteristic using cross‐coupling has been proposed. © 2013 Wiley Periodicals, Inc. Int J RF and Microwave CAE 24:360–366, 2014.  相似文献   

14.
A novel band‐stop filter with single‐loop split ring resonators (SRRs) is proposed for spoof surface plasmon polaritons (SPPs) at millimeter wave frequencies, achieving a miniaturized size of 0.052λ0 × 0.278λ0 at its resonant frequency. The SRRs provide both a low‐pass response as the rectangular corrugations used in the conventional SPPs and an additional band‐stop response induced by the resonance of SRRs. To verify this design, a back‐to‐back device with two coplanar waveguides as the input and output feeding was fabricated and characterized, the measured S‐parameters of which agree well with the simulation. The measured stop band is centered at 49 GHz with a ?10‐dB bandwidth of 4.1 GHz and a high Q‐factor of 93, in which the maximum attenuation is 31 dB. The filter has a low insertion loss of less than 2.8 dB in the pass band. Such approaches may find many applications to achieve compact millimeter wave circuits.  相似文献   

15.
This article presents a systematic design procedure of CPW‐based Composite Right/Left‐Handed Transmission Line (CRLH TL), including the initial design and optimization algorithm. A Graphical User Interface (GUI) is provided to help inexperienced users synthesize CRLH at any given transition frequency, without tedious tuning or iterative trial. An improved fitness function based on Genetic Algorithm (GA) is presented to reduce the return loss and diminish the bandgap. This design procedure is fast and available, and has been verified by both measurement and full‐wave simulation results. © 2011 Wiley Periodicals, Inc. Int J RF and Microwave CAE, 2011.  相似文献   

16.
This article reports a novel bandpass filter using modified half mode substrate integrated waveguide technique. The via‐fences are deployed as impedance inverters for the proposed filter to reduce its footprints, which are extracted by using a full‐wave electromagnetic simulator HFSS for the filter design. Detailed design procedure is discussed. A bandpass filter having a center frequency of 10.03 GHz and a pass band from 9.78 to 10.3 GHz is designed for demonstration, and experiments are carried out for the validation. Good agreements between experiment and simulated results are obtained, which show that the proposed filter has a compact size, a low insertion loss, and a high selectivity. It is attractive for the radio communication system. © 2014 Wiley Periodicals, Inc. Int J RF and Microwave CAE 25:277–281, 2015.  相似文献   

17.
In this paper, the exponential H filter design problem is investigated for a general class of stochastic time‐varying delay system with Markovian jumping parameters. The stochastic uncertainties appear in both the dynamic and the measurement equations and the state delay is assumed to be time‐varying. Attention is focused on the design of mean‐square exponentially stable and Markovian jump filter such that the filtering error systems are mean‐square exponentially stable and the estimation error satisfies a given H performance. By introducing some slack matrix variables, delay‐dependent sufficient conditions for the solvability of the above problem are presented in terms of linear matrix inequalities (LMIs). In addition, the decay rate can be a given positive value without any other constraints. When the proposed LMIs are feasible, an explicit expression of the desired H filter can be given. A numerical example is provided to illustrate the effectiveness of the proposed design approach. Copyright © 2009 John Wiley & Sons, Ltd.  相似文献   

18.
A compact, band‐pass filter utilizing multi‐element resonators, structured from sections of distributed transmission lines, is presented. A band‐pass filter design procedure is established that emphasizes CAD techniques to characterize the individual resonators and to determine the resonator coupling values required for a specified pass‐band response. Detailed band‐pass filter design examples are illustrated and simulation results are employed to validate the design procedure. © 2003 Wiley Periodicals, Inc. Int J RF and Microwave CAE 13, 447–458, 2003.  相似文献   

19.
Nonlinear limits for single-crystal silicon microresonators   总被引:1,自引:0,他引:1  
Nonlinear effects in single-crystal silicon microresonators are analyzed with the focus on mechanical nonlinearities. The bulk acoustic wave (BAW) resonators are shown to have orders-of-magnitude higher energy storage capability than flexural beam resonators. The bifurcation point for the silicon BAW resonators is measured and the maximum vibration amplitude is shown to approach the intrinsic material limit. The importance of nonlinearities in setting the limit for vibration energy storage is demonstrated in oscillator applications. The phase noise calculated for silicon microresonator-based oscillators is compared to the conventional macroscopic quartz-based oscillators, and it is shown that the higher energy density attainable with the silicon resonators can partially compensate for the small microresonator size. Scaling law for microresonator phase noise is developed.  相似文献   

20.
This paper investigates robust and reliable H filter design for a class of nonlinear networked control systems: (i) a T‐S fuzzy model with its own uncertainties is used to approximate the nonlinear dynamics of the plant, (ii) a new sensor failure model with uncertainties is proposed, and (iii) the signal transfer of the closed‐loop system is under a networked communication scheme and therefore is subject to time delay, packet loss, and/or packet out of order. Four new theorems are proved to cover the conditions for the robust mean square stability of the systems under study in terms of LMIs, and a decoupling method for the filter design is developed. Two examples, one of them is based on a model of an inverted pendulum, are provided to demonstrate the design method. Copyright © 2011 John Wiley & Sons, Ltd.  相似文献   

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