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Based on the comprehensive analysis about the hydrogeological condition, ecological environment, and the characteristics of geological environment, energy is devoted to constructing a function evaluation indicator system of shallow groundwater with Jinjiang regional characteristic in the light of the assessment indicator system proposed in technical requirement for function evaluation and zoning of shallow groundwater issued by ministry of Land and resources. By dint of expert’s knowledge and experience, efforts are spent in assigning different weight values to the indicators, classifying function evaluation grading standards, and putting forward a secondary function zoning rating system. Besides, focus is put on building a comprehensive function evaluation model of shallow groundwater by means of analytic hierarchy process based on the constructed assessment indicator system of shallow groundwater. In order to guarantee assessment accuracy, the studied region is split into regular discrete grid for the purpose of calculating the comprehensive assessment index of grid unit. Meanwhile, based on GIS’ spatial analysis function, a research is conducted on the overall function zoning map of the shallow groundwater in the studied region to accurately reveal its spatial distribution and exploitation and provide scientific basis for groundwater management.

An innovated fabricated process of the flexible surface acoustic wave (SAW) device is proposed in this study. Fully inkjet printing and sol-gel technology are used in this fabricated process. The flexible SAW device is composed of a ZnO layer sandwiched in between a flexible polyimide plastic sheet and two sets of interdigital transducers layer. The material of the top interdigital transducer layer is nano silver. The ZnO solution is prepared by sol-gel technology. Both the ZnO and top interdigital transducer layers are deposited by inkjet printing. The fully inkjet printing process possesses the advantages of direct patterning and low-cost. It does not require photolithography and etching processes since the pattern is directly printed on the flexible sheet. The center frequency of this prototype is matched with the design frequency. The prototype demonstrates that the presented flexible SAW device is available for the possible application in future. It may be applied to the sensing on curve surface.

An efficient and practical design method for a dual-band bandpass filter (BPF) is presented. The electrical specifications of the filter, such as the center frequency, bandwidth, and transmission zero location, are controllable and adjustable. Once, the desired ratio of the resonant frequency of the two bands is given, the characteristic impedance of the line corresponding to the specific ratio can be accurately determined from the design curve. Compared with the conventional half- and quarter-wavelength stepped-impedance resonators (SIRs), the proposed unequal-length shunted-line stepped- impedance resonator (shunted-line SIR) can provide an efficient way to realize the dual-band filter, especially when two passbands are closely spaced. Furthermore, the multitransmission zeros and one controllable transmission zero are generated near the passbands to improve the out-of-band rejection. The design examples of microstrip dual-band BPFs operating at 2.2/3.45 and 1.95/2.65 GHz with equal absolute bandwidths and high isolation are demonstrated to validate of the design method. In the illustrated cases, a small frequency ratio of 1.3 between two resonant frequencies can be achieved. The proposed design method is very useful for the dual-band BPF design, especially when the two passbands are very close.

This article provides an extensive review of dual-band bandpass filter designs and discusses the pros and cons of these design methods. The behavior of an SLSIR proposed by the authors shows that two passbands can be generated without using external dual-band impedance transformers. Furthermore, by using the design curves shown in this article, the k and the Qe, which are used for the synthesis of a dual-band bandpass filter, can be accurately calculated. Two examples of dual-band bandpass filters operated at 1.9/5.7 and 2.45/5.7 GHz with different bandwidths was presented to show details of the design technique. The simulation and measurement results shown are in good agreement. The resulting SLSIR dual-band filters using this technique not only provide controllable responses but also have high frequency selectivity and good impedance matching with considerable size reduction. Finally, a performance comparison comparing the technique in this article with previous design methods is listed in Table 3. The design methodology should be useful in dual-band RF transceiver design.

This article presents a V-band high-isolation complementary metal-oxide semiconductor (CMOS) single-pole double-throw transmitter/receiver (T/R) switch fabricated with TSMC standard 90-nm 1P9M CMOS technology. A low insertion loss and high linearity are achieved using the body-floating technique. In addition, the leakage cancellation technique is used to increase the isolation between the transmitter and receiver ports. The measured results show the insertion loss from the transmitter port to the antenna port is less than 3.5 dB, and the isolation between the transmitter and receiver ports is higher than 28 dB from 57 to 64 GHz. At the center frequency of 60 GHz, the port isolation is higher than 34 dB. The switch isolation has also been measured under the large signal test which is not reported in the previous works. © 2012 Wiley Periodicals, Inc. Microwave Opt Technol Lett 54:1118–1123, 2012

This article presents a 77-GHz miniaturized on-chip bandpass filter using a 0.18-μm standard CMOS process. At first the stepped impedance resonator is used to reduce the length of the stub resonator. Then the slotted ground slow-wave structure (SGSWS) is applied for further reducion of the overall component size. The size of the designed filter with SGSWS is smaller than that of the original stub filter with a size reduction of 40% when operating at the same resonant frequency. The simulated and measured results are in good agreement. The return loss is better than 15 dB within the passband and a low insertion loss of 2.9 dB is obtained. © 2012 Wiley Periodicals, Inc. Microwave Opt Technol Lett 54:1063–1066, 2012; View this article online at wileyonlinelibrary.com. DOI 10.1002/mop.26693

A novel bandpass filter (BPF) based on the composite right/left-handed (CRLH) material and 0◦ feeding structure is proposed. With multiple unit-cells cascaded, the new section comprises the series interdigital capacitors and the shunt short-circuited stub inductors in the symmetric configuration. The circuit is designed to be unbalanced, a tunable gap between left handed and right handed modes in the β − ω diagram can control out of band performance. With careful design, a bandpass filter with wide rejection band can be achieved. Furthermore, by using the 0◦ feeding associated structure, two extra transmission zeros are created just outside the intended passband. Finally, a three cells bandpass filter has been designed and fabricated with 1.1 dB insertion loss at the center frequency of 4.2GHz. Two transmission zeros are located at 2.95 GHz and 6.18 GHz with attenuations of −44.1 dB and −37.3 dB, respectively. Also, a wide rejection band from 5.4 to 9GHz is obtained. Received 5 October 2010, Accepted 28 October 2010, Scheduled 8 November 2010 Corresponding author: Chu-Yu Chen (cychen57@mail.nutn.edu.tw). 164 Chou, Tsai, and Chen

This paper presents a small printed monopole antenna of size 10 × 29 × 0.8 mm3. The proposed antenna consists of a rectangular radiating patch on one side and a rectangular ground metal with an inverted L-shaped ground strip on the other side. With this simple structure, the proposed antenna provides an impedance bandwidth ranging from 3.05 to 5.82 GHz, which covers the wireless USB (WUSB) operation band of 3.1–4.85 GHz. Good radiation performance and low gain variation are also obtained using the proposed antenna. Equipping with the advantages of dimension and performance, the proposed antenna appears as a promising candidate for USB dongle application. The detail of the proposed antenna design and experimental results obtained thereafter are presented and discussed in this article.

This article presents design and implementation of a 60-GHz millimeter- wave on-chip bandpass filter using a 0.18-μm standard CMOS process. The asymmetric compact microstrip resonator cell structure is used to design the filter with two transmission zeros. The input and output capacitors using multilayer coupling are added to create the passband. The die size of the chip is 0.85 × 0.64 mm2. The filter has a 3-dB bandwidth of about 15 GHz at the center frequency of 64 GHz. The measured insertion loss of the center-frequency is about 3.9 dB and the return loss is better than 10 dB within passband. The designed on-chip filter is useful for the integrated design of the 60-GHz CMOS single-chip RF transceiver. © 2009 Wiley Periodicals, Inc. Microwave Opt Technol Lett 51: 597–600, 2009; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/mop.24119

A novel 60-GHz wideband Marchand balun fabricated with a standard 0.18 μm six-metal-layer CMOS process for millimeter-wave applications is presented. A technique for achieving good balance with the fourth metal layer microstrip conductor is used in the designed Marchand balun. The fabricated CMOS balun uses multilayer coupling with the top two layers. An output matching network is added to improve the output return loss. The measured amplitude imbalance was about ±1.5 dB from 25 to 65 GHz, over the 89% operating frequency band. © 2009 Wiley Periodicals, Inc. Microwave Opt Technol Lett 51: 766–770, 2009; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/mop.24176

In this paper, coupled open stub circuits are applied for providing band notch in filter design. Even- and odd-mode excitations for a coupled line can be represented as the equivalent capacitance networks. The rejection bandwidth of the designed filter can be controlled by the mutual capacitance Cm . An ultra-wideband (UWB) bandpass filter with 5 GHz to 6 GHz rejection band is proposed. To inhibit the signals ranged from 5 to 6 GHz, two pairs of stepped-impedance coupled open stubs are implemented on the multiple-mode resonator (MMR) The designed UWB filter has two transmission bands. The first passband from 2.8 GHz to 5 GHz has less than 0.8 dB magnitude of insertion loss and greater than –15 dB return loss. The second passband within 6 GHz and 10.6 GHz has less than 1.5 dB magnitude of insertion loss and greater than 15 dB return loss. The rejection at 5.5 GHz is better than 50 dB. This filter can be integrated in UWB radio systems and efficiently enhance the interference immunity from WLAN.

A 3–10 GHz broadband CMOS T/R Switch for ultra-wideband (UWB) transceiver is proposed. This broadband CMOS transmit/receive (T/R) Switch is fabricated based on the 0.18 μm 1P6M standard CMOS process. On-chip measurement of the CMOS T/R Switch is performed. The insertion loss of the proposed CMOS T/R Switch is about 3.1 ± 1.3 dB. The return losses at both input and output terminals are higher than 14 dB. It is also characterized with 25–34 dB isolation and 18–20 dBm input P1dB. The broadband CMOS T/R Switch shows highly linear phase and group delay of 20 ± 10 ps from 10 MHz to 15 GHz. It can be easily integrated with other CMOS RFICs to form on-chip transceivers for various UWB applications. © 2007 Wiley Periodicals, Inc. Microwave Opt Technol Lett 50: 457–460, 2008; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/mop.23129

This paper presents a novel, compact, low-insertion-loss, sharp-rejection, wideband microstrip bandpass filter. The filter is based on a ring resonator with direct-connected orthogonal feed lines, and uses two stepped-impedance open stubs to construct a wideband passband with two sharp stopbands. The unit cell of the ring resonators is easily cascaded and also has the feature of a compact structure. The filter is designed to reduce interference in full-duplex systems for satellite communications. © 2005 Wiley Periodicals, Inc. Microwave Opt Technol Lett 45: 312–315, 2005; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/mop.20807

A compact microstrip dual-band bandpass filter (BPF) using the embedded open-loop ring resonator is proposed. The filter can achieve two passbands without using the external dual-band impedance transformer in the input/output feeding line. Furthermore, by using the developed design method, the ratio of the first passband to the second passband can be controlled. A compact microstrip dual-band BPF operated at 2.45/5.7 GHz is demonstrated. The designed filter has low insertion loss, high rejection between the two passbands, and a very small size of 11.5 × 4.65 mm2 (0.094λ0 × 0.039 λ0), λ0 being the free-space wavelength of the center operating frequency of the 2.45 GHz. The good agreement between simulation and measurement is obtained.

This letter presents the design and implementation of a 24-/60-GHz millimeter-wave dual-band on-chip bandpass filter using a 0.18-mum standard CMOS process. The concept of quarter-wavelength stepped-impedance resonator (lambda/4 SIR) is utilized to realize stopband characteristics at desired frequencies and reduce the chip size. The structure of the open-circuited dual-behavior resonators (OC-DBRs) produces one passband with two transmission zeros on either side. The size of the designed filter is 1.030 times 0.590 mm2.

This letter presents the design and implementation of a 70 GHz millimeter-wave compact folded loop dual-mode on-chip bandpass filter (BPF) using a 0.18 mum standard CMOS process. A compact BPF, consisting of such a planar ring resonator structure having dual transmission zeros was fabricated and designed. The size of the designed filter is 650 X 670 mum2. Calculated circuit model, EM simulated and measured results of the proposed filter operating at 70 GHz are shown in a good agreement and have good performance. The filter has a 3-dB bandwidth of about 18 GHz at the center frequency of 70 GHz. The measured insertion loss of the passband is about 3.6 dB and the return loss is better than 10 dB within the passband.

A new dual-band planar filter has been proposed. It is shown that the two transmission bands can be excited and designed using proposed resonators which combine different sizes of open-loop resonators. The main resonators control the low-band resonant frequency and the sub resonators control the high-band resonant frequency. With dual-feeding structures added, the performances of the filter such as frequency selectivity and insertion loss are much improved. The embedded resonators structure can further miniaturize the dimensions of the overall structure. The proposed dual-band filter will find applications in wireless communication circuits

A new type of novel low loss dual-band microstrip filters using folded open-loop ring resonators (OLRRs) is presented in this letter. Both magnetic and electric coupling structures are implemented to provide high performance passband response. The first passband and second passband of the designed dual-band filter can be easily and accurately shifted to a desired frequency band by adjusting the physical dimensions of OLRRs. Finally, the 2.4-GHz/5.7-GHz and 2.4-GHz/5.2-GHz dual-band filters are illustrated and measured in this letter.

A novel miniaturized microstrip-line filter using a pair of interlocking resonators is proposed. To reduce the size dimensions and suppress the spurious responses simultaneously, a stepped-impedance structure is integrated into this new proposed filter. The cross-coupling effect can be created in this designed filter. Furthermore, the filter has two transmission zeros on both sides of the passband. The full-wave simulator IE3D is used to design and simulate the interlocking resonators bandpass filter. The design is been verified by the experiment results. © 2005 Wiley Periodicals, Inc. Microwave Opt Technol Lett 47: 261–263, 2005; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/mop.21141

This paper presents a 60GHz high-isolation CMOS single-pole double-throw (SPDT) transmitter/receiver (T/R) switch fabricated with TSMC standard 90-nm 1P9M CMOS technology. A low insertion loss and high linearity are achieved by using the body-floating technique. The leakage cancellation technique is used to increase the isolation between the transmitter and receiver ports. The top metal (M9) is mainly adopted for designing signal paths and the microstrip-line matching elements. In order to minimize the substrate loss, the first metal (M1) as the ground plane is used in this design. The measured results show the insertion loss from the transmitter port to the antenna port is less than 3.5 dB, and the isolation between the transmitter and receiver ports is higher than 28 dB from 57 to 64GHz. At the center frequency of 60GHz, the port isolation is higher than 34 dB and the input 1-dB compression point (IP1dB) is +6.9 dBm.

In this paper, a new statistical analysis method is presented to investigate the effect of nine factors in the 65nm MOSFET structure. The aim of this work is to clarify the electrical properties, correlation of the principal factors, based on exploratory factor analysis (EFA). From the simulation result, optimization parameters are determinative to achieve the objective.

A detailed analysis of the transient response of an electromagnetic pulse (EMP) and a Gaussian pulse in anisotropic laminated composites is presented. To this end, both the equivalent transmission line circuit (ETLC) model and the finite-difference-time-domain (FDTD) method are adopted in the time-domain analysis. Numerical results are presented for graphite/epoxy laminates, based on a model which treats each lamina as a homogeneous and anisotropic sheet. The factors that influence the transient response of anisotropic laminated composites, such as laminate thickness, fiber orientation, and the angle, frequency contents, and polarization of the incident wave, are also investigated. >

This letter presents the design and implementation of a 77-GHz millimeter-wave on-chip bandpass filter with balanced output that was fabricated using a TSMC 0.18-μm standard CMOS process. The performances of the single-ended and single-ended-to-differential bandpass filters are simulated and measured. The chip size of the designed filter is 0.55 × 0.7 mm2. The simulated and measured results of the proposed filter are found to be in good agreement. The filter has a 3-dB bandwidth of about 14 GHz at a center frequency of 77 GHz. The measured insertion loss of the passband is about 6 dB and includes a 3-dB splitting loss; the return loss is less than 10 dB within the passband.

A 26-/77-GHz dual-band branch-line coupler fabricated using standard 0.18-µm CMOS technology is presented. The dual-band coupler is with a compact size of 1.0 × 1.0 mm2. The simulated frequency response is to 110 GHz. The measured frequency response shows a good performance with amplitude and phase imbalnce of ± 0.5 dB and ± 5°, respectively, in the low band. The S 21 in the high band is about 7.5 dB The measured isolation and the return loss are better than 15 dB within the two passbands. The on-chip coupler will be useful for the integrated design of a 26/77-GHz CMOS single-chip RF transceiver.

A planar printed multiband handset antenna by using an L-shape radiating element and an open-loop resonator to achieve multi-operation bands is presented. The antenna can cover the operation of GSM900/DCS1800 and WLAN2450 or Bluetooth system. The antenna is fabricated with a FR-4 substrate. The areas occupied by the antenna radiators and ground plane are 15×45 mm2 and 85×45 mm2, respectively. The area of antenna substrate has 100×45 mm2 which is a typical size of mobile handsets. The HFSS FEM-based 3-D full-wave EM solver is used for the design simulation. For the triple-band antenna, except for the GSM900 system, the measured antenna input VSWR is less than 3.5 in the designed frequency bands. The measured maximum antenna gains are about 0.8, 2.4, and 2.2 dBi at 920 MHz, 1795, and 2450 MHz, respectively. The antenna has the advantages of low-cost, easy-fabrication, and an integration with RF front-end circuits.

A full-wave analysis of a coplanar waveguiding structure with multiple dielectric layers is presented. The results of a hybrid approach that combines the finite-element method and the conformal-mapping technique are compared with those of the spectral-domain approach. Numerical results for effective dielectric constants, characteristic impedances, current distributions, and field distributions for various multilayer coplanar line structures are presented and discussed. The computed results are compared with the available quasi-static ones. >

This paper presents the design and implementation of a compact and broadband 70-GHz millimetre-wave RFIC-on-chip bandpass filter using a 0.18-mum standard CMOS process. A novel bandpass filter, consisting of such a planar ring resonator structure having dual transmission zeros was fabricated and designed. The size of the designed filter is 650 times 670 mum2. Simulated and measured resulted of a compact and broadband bandpass filter operating at 70-GHz is shown to have good performance. The filter has a 3-dB bandwidth of about 18 GHz at the center frequency of 70 GHz. The measured insertion loss of the passband is about 3.6 dB and the return loss is better than 10 dB within passband.

A novel ultra-wideband (UWB) bandpass filter with 5 to 6 GHz rejection band is proposed. The multiple coupled line structure is incorporated with multiple-mode resonator (MMR) to provide wide transmission band and enhance out-of band performance. To inhibit the signals ranged from 5- to 6-GHz, four stepped-impedance open stubs are implemented on the MMR without increasing the size of the proposed filter. The design of the proposed UWB filter has two transmission bands. The first passband from 2.8 GHz to 5 GHz has less than 2 dB insertion loss and greater than 18 dB return loss. The second passband within 6 GHz and 10.6 GHz has less than 1.5 dB insertion loss and greater than 15 dB return loss. The rejection at 5.5 GHz is better than 50 dB. This filter can be integrated in UWB radio systems and efficiently enhance the interference immunity from WLAN.

This paper presents design and implementation of a 60-GHz millimeter-wave RFIC-on-chip bandpass filter with a 0.18-mum standard CMOS process. A planar ring resonator structure with dual transmission zeros was adopted to design this CMOS filter. The die size of the chip is 1.148 times 1.49 mm2. The measured insertion loss of a designed bandpass is less than 5 dB from 59 to 68 GHz. The investigations of sensitivity to the insertion loss and the passband bandwidth for different perturbation stub sizes are also studied. The filter has a 5-dB bandwidth of about 9 GHz at the center frequency of 64 GHz. The measured insertion loss of the passband is about 4.9 dB and the return loss is better than 10 dB within passband.

A new dual-band planar filter has been proposed. It is shown that the two transmission bands can be excited and designed using proposed resonators which combine different size of open-loop resonators. The main resonators control the low- band resonant frequency and the sub resonators control the high- band resonant frequency. Two passbands can be easily and flexibly designed by adjusting the length of resonators. The proposed dual-band filter will find applications in wireless communication circuits.

The authors present an analysis of plane-wave reflection from stratified anisotropic lossy media. To this end, an equivalent-transmission-line-circuit model is adopted in the frequency- and time-domain analysis. The reflection properties of graphite/epoxy, boron/epoxy, Kevlar/epoxy and their hybrid laminated composites are investigated in detail. >

Compared with the conventional log-periodic balun, the design of a symmetric log-periodic balun can provide better performance over the entire designed band. A novel ultra-wideband (UWB) balun with 3–6 GHz passband is demonstrated for UWB applications. The problems of fabrication and measurement of the conventional log-periodic balun operated at higher frequency problems can be further improved. The magnitude and phase difference between two output ports are kept balancing at higher band edge portion. The measured amplitude imbalance is about ±1.1 dB with a corresponding phase difference about ±4°. The bandwidth of the balun is around 70%. © 2008 Wiley Periodicals, Inc. Microwave Opt Technol Lett 50: 947–948, 2008; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/mop.23264