Showing papers in "IEEE Microwave and Wireless Components Letters in 2012"
TL;DR: In this article, a chipless RFID tag operating in the frequency span 2 to 4 GHz is presented, which does not require any ground plane and it is made of 20 scatterers giving 20 b as coding capacity, for a compact size of 70 25.
Abstract: This article presents a new chipless RFID tag operating in the frequency span 2 to 4 GHz. In particular the tag does not require any ground plane and it is made of 20 scatterers giving 20 b as coding capacity, for a compact size of 70 25 , compatible with a credit-card format. Its fabrication process is potentially very cheap because it needs only one conductive layer, so that it can be fully printed directly on the product. To overcome the detuning effect inherent to a single layer tag and make this design robust to the environment versatility, a simple compensation technique is introduced and experimented for the first time. Measurements have been performed frequency domain, using amplitude and the group delay response. The exploitation of group delay appears to be very reliable and promising way to retrieve the coded information.
161 citations
TL;DR: In this article, a tri-band bandpass filter designed based on a stub-loaded step-impedance resonator (SIR) is proposed, where the center frequencies are 1.575, 2.4, and 3.5 GHz.
Abstract: A tri-band bandpass filter designed based on a stub-loaded step-impedance resonator (SIR) is proposed. The resonant behavior of the stub-loaded SIR is analyzed. By properly controlling the impedance ratio K1, the length ratio (α) and the length ratio (r) of the stub-loaded SIR, the center frequencies are designed at 1.575, 2.4, and 3.5 GHz, respectively, corresponding to the GPS, WLAN and WiMAX applications. Furthermore, a 0° feed structure is used to provide at least one transmission zero near passband edge of each passband, resulting in high selectivity. Experimental results show good agreement with the simulated results.
124 citations
TL;DR: In this article, a vector-fitting technique was used to expand the permittivity of graphene into a rational function series of complex conjugate pole-residue pairs, which is implemented into FDTD by an auxiliary differential equation formulation.
Abstract: Graphene-based devices constitute a pioneering field of research for their extraordinary electromagnetic properties. The incorporation of appropriate models into numerical simulators is necessary in order to take advantage of these properties. In this work, we propose a method to incorporate graphene-sheet models into the FDTD method. The use of vector-fitting techniques expands the permittivity of graphene into a rational function series of complex conjugate pole-residue pairs, which is implemented into FDTD by an auxiliary differential equation formulation. Simple waveguiding problems validate our approach.
111 citations
TL;DR: In this article, a differential-mode wideband bandpass filter (BPF) with enhanced common-mode suppression using a slotline resonator is presented, and the insertion loss of the CM signals is higher than 475 dB, the fractional bandwidth defined by the 10 dB return loss for the (DM) signals is about 105%.
Abstract: A novel design of a differential-mode (DM) wideband bandpass filter (BPF) with enhanced common-mode (CM) suppression using a slotline resonator is presented The BPF consists of two pairs of parallel microstrip transmission lines, a pair of transverse microstrip sections connected to the transmission lines, and a longitudinal slotline resonator placed in the ground plane With proper placement of the slotline resonator, the mode coupling between the slotline mode and the (DM) signals can be maximized, while that between the slotline mode and the CM signals can be minimized It is found that throughout the (DM) passband, the insertion loss of the CM signals is higher than 475 dB, the fractional bandwidth defined by the 10 dB return loss for the (DM) signals is about 105%, and the insertion loss for the (DM) signals ranges from 122 to 582 dB over the fractional bandwidth Good agreement between simulated and measured results is obtained
111 citations
TL;DR: In this paper, simulations and measurement results are presented for another version called microstrip gap waveguide, working as inverted microstrip line and realized using a mushroom-type EBG surface.
Abstract: The gap waveguide has been recently presented as a new transmission line technology using artificial magnetic conductors (AMCs) to allow the wave propagation only along a desired path. The first validation has been provided using a lid of metal pins as AMC for high frequency applications. In this letter, simulations and measurement results are presented for another version called microstrip gap waveguide, working as inverted microstrip line and realized using a mushroom-type EBG surface. The transmission line is surrounded by mushrooms which create a parallel plate stop band, suppressing cavity modes and unwanted radiations compared to standard packaged microstrip transmission lines. The field propagates in the air gap between the upper lid and the mushrooms layer, providing a low loss compact circuit made in printed technology.
108 citations
TL;DR: In this article, a new sensor based on complementary split-ring resonators is presented to detect sub-millimeter surface cracks, which is based on perturbing the electromagnetic field around an electrically small resonator, thus initiating a shift in the resonance frequency.
Abstract: A new sensor based on complementary split-ring resonators is presented to detect sub-millimeter surface cracks. The sensing mechanism is based on perturbing the electromagnetic field around an electrically small resonator, thus initiating a shift in the resonance frequency. The sensor is simple to fabricate and inexpensive as it is etched out in the ground plane of a microstrip-line using printed circuit board technology. The sensor exhibits a frequency shift of more than 240 MHz for a 100 μm crack.
104 citations
TL;DR: In this article, the authors demonstrate over 1 mW power generation at 300 GHz with a uni-travelling-carrier photodiode (UTC-PD) packaged in a WR-3 waveguide module.
Abstract: In this letter, we demonstrate over 1 mW power generation at 300 GHz with a uni-travelling-carrier photodiode (UTC-PD) packaged in a WR-3 waveguide module. To increase the maximum power, two identical UTC-PDs were monolithically integrated along with a T-junction to combine the power from the two PDs. The UTC-PD module exhibited peak saturated output power of approximately 1.2 mW at 300 GHz with photocurrent of around 20 mA per PD and bias voltage of -3.9 V. In addition, 3 and 10 dB bandwidths were measured to be around 70 GHz or 23% and over 150 GHz or 50%, respectively.
102 citations
TL;DR: In this paper, a compact differential ultra-wideband (UWB) bandpass filter with planar structure is presented, and the circuit of the proposed filter is analyzed, showing that the differential-mode circuit, which consists of two short-ended stubs and an open-ended parallel-coupled lines, performs as a UWB BPF.
Abstract: A compact differential ultra-wideband (UWB) bandpass filter (BPF) with planar structure is presented. The circuit of the proposed filter is analyzed, showing that the differential-mode circuit, which consists of two short-ended stubs and an open-ended parallel-coupled lines, performs as a UWB BPF. While the common-mode circuit performs as a UWB bandstop filter, and the common-mode responses are suppressed across the whole UWB differential passband. A microstrip differential UWB BPF is designed, simulated and measured. Simulated and measured results show that the proposed filter has compact size (0.35λg×0.7λg), UWB differential passband (3 dB fractional bandwidth 119%) and UWB common-mode suppression (-10 db attenuation across 2.6-12 GHz).
92 citations
TL;DR: In this paper, a floating variable negative impedance converter (NIl) was proposed for susceptance cancellation for slot antennas and artificial magnetic conductors using IBM 8 HP BiCMOS process with inductance that tunes from -64 to -40 nH.
Abstract: A floating variable Negative Impedance Inverter (NIl) circuit is proposed that is derived from Linvill's unbalanced negative impedance converter. A negative-inductance Integrated Circuit (IC) has been realized using the IBM 8 HP BiCMOS process with an inductance that tunes from -64 to -40 nH. The IC is short-circuit-stable (which has been verified by experiment) and is dc coupled at the terminals, making it directly applicable to susceptance cancellation for slot antennas and artificial magnetic conductors. This letter reports the circuit topology, measurement technique, and measured data.
83 citations
TL;DR: In this article, a new 5 GHz band-notched balanced ultra-wideband (UWB) bandpass filter (BPF) was designed using a stepped-impedance slotline multi-mode resonator (MMR).
Abstract: This letter presents a new 5 GHz band-notched balanced ultra-wideband (UWB) bandpass filter (BPF), which is designed using a stepped-impedance slotline multi-mode resonator (MMR). To obtain favorable uniform differential-mode (DM) response, a microstrip-to-slotline transition is used as the signal-feeding structure and the first three resonant modes of the slotline MMR are located in the UWB passband. Common-mode (CM) signal rejection is achieved by deploying the slotline MMR in such a way that the quarter-wavelength resonances occurring near the input and output sides of the resonator are well decoupled. Also featured in this design is the blocking of unwanted WLAN signals, which is achieved by loading the input feed-lines with a stepped-impedance microstrip stub to create a notch-band centered at 5.5 GHz. The designed BPF has a measured minimum DM insertion loss of 0.83 dB in the UWB passband, in which the measured CM suppression is larger than 18.85 dB.
82 citations
TL;DR: In this paper, a simple and efficient method has been presented to design multi-band microstrip bandpass filters (BPFs) without a significant increase in circuit size, which can be used to implement a third order BPF with a transmission zero at the upper side of the passband when these resonant frequencies are suitably assigned.
Abstract: A simple and efficient method has been presented to design multi-band microstrip bandpass filters (BPFs) without a significant increase in circuit size. By utilizing multiple coupling paths, all passbands can then be fully controlled and, thus, the design is flexible so as to independently realize different bands. In addition, by adjusting the structural parameters of the proposed trimode stub-load stepped-impedance resonator, its first three resonant frequencies can be controlled. Thus, it can be utilized to implement a third-order BPF with a transmission zero at the upper side of the passband when these resonant frequencies are suitably assigned. For our demonstration, a compact quint-band BPF formed by only five tri-mode resonators has been designed and fabricated. It is shown that the quint-band filter occupies an extremely small area, i.e., 0.34 λ0 by 0.03 λ0 (0.52 λgby 0.045 λg). Good agreement is also achieved between simulation and measurement.
TL;DR: In this article, two $K$ -band cross-coupled substrate integrated waveguide (SIW) filters with improved stopband performance are proposed, where two additional transmission zeros (TZs) are introduced for each filter, and two additional TZs are introduced and the stop band performance is then improved.
Abstract: In this letter, two $K$ -band cross-coupled substrate integrated waveguide (SIW) filters with improved stopband performance are proposed. To implement the negative coupling, ${\rm TE}_{201}$ -mode response is used in the first cavity, which is also used to implement cross-coupling with ${\rm TE}_{101}$ mode for generating additional transmission zeros (TZs) in the stopband of the filters. For each filter, two additional TZs are introduced and the stopband performance is then improved. The TZ provided by the first cavity can be introduced either below or above the passband, while the TZ provided by the fourth cavity can only be introduced above the passband. The two novel SIW filters are designed at the same center frequency of 20 GHz with the same bandwidth of 600 MHz. The measured data agree well with the simulated results.
TL;DR: In this paper, a radial stub loaded resonator (RSLR) is proposed to control two tunable transmission zeros separately and on the other hand, has the ability to provide a notched band.
Abstract: In this letter, a novel compact ultra-wideband (UWB) microstrip bandpass filter (BPF) with a notched band is presented by using the proposed radial stub loaded resonator (RSLR). The RSLR, on the one hand, is able to control two tunable transmission zeros separately and on the other hand, has the ability to provide a notched band. In addition, the vertical dimension of the UWB BPF can be significantly reduced by using RSLR, as compared with the UWB BPF based on the conventional stub-loaded resonator (SISLR). For validation, two UWB BPFs, one without the notched band and the other with a notched band at 8.0 GHz for rejecting satellite-communication signal, are developed and fabricated. Measured results show two fabricated filters have the merits of low insertion losses, sharp rejections and flat group delays. Moreover, two filters exhibit the simple topologies and compact sizes.
TL;DR: In this article, a tuned-shunt topology is used to minimize the insertion loss, and the transistor layout results in very low ground inductance and high isolation for 140-220 GHz single-pole single-throw (SPST) switches built using 45 nm semiconductor-on-insulator (SOI) technology.
Abstract: This letter presents 140-220 GHz single-pole single-throw (SPST) and single-pole double-throw (SPDT) switches built using 45 nm semiconductor-on-insulator (SOI) CMOS technology. A tuned-shunt topology is used to minimize the insertion loss, and the transistor layout results in very low ground inductance and high isolation. The double-shunt SPST switch results in an insertion loss of 1.0 dB and an isolation of 20 dB, while the SPDT switches result in an insertion loss of 3.0 dB and an isolation of 20-25 dB, all at 180 GHz. The switches are well matched with a return loss at all ports greater than 10 dB at 140-220 GHz. The work shows that advanced CMOS nodes can be used for transmit-receive switches in emerging 140-220 GHz CMOS systems.
TL;DR: In this paper, a three-pole 5% FBW Chebyshev filter has been designed, fabricated and measured, and the fabricated device shows an excellent agreement with simulated results.
Abstract: In this letter, the design and experimental results of compact low loss combline filters, based on the extension of the classical coaxial waveguide resonator to Substrate Integrated Waveguide (SIW) technology, are succesfully demonstrated. A three-pole 5% FBW Chebyshev filter has been designed, fabricated and measured. The fabricated device shows an excellent agreement with simulated results. These structures keep the low-cost fabrication scheme of single-layer PCB processing, while requiring less than half the area compared to a conventional SIW design.
TL;DR: In this article, a quadruplemode resonator bandpass filter with tunable bandwidth is proposed, where two types of microwave varactors are used to tune the resonant frequencies and transmission zeros (TZs).
Abstract: In this letter, a novel quadruple-mode resonator bandpass filter (BPF) with tunable bandwidth is proposed. By using two types of microwave varactors to tune the resonant frequencies and transmission zeros (TZs), the high-side edge of the passband and low-side edge of the passband can be separately varied. Therefore, the bandwidth could be tunable with reasonable adjust of the values of varactors. Theoretical expressions have been derived for the resonant frequencies and the TZs. The measured results of the BPF show that the fractional bandwidth can be tuned from 22% to 34% at a fixed centre frequency 2.0 GHz with a return loss better than dB. The tested results show good agreement with simulated results.
TL;DR: In this paper, a planar microstrip crossover junction with vias is presented. And the CB-CPW structure is employed as the core part of the crossover design, which has a bandwidth from 10 up to 6000 MHz for 20 dB return loss, 1 dB insertion loss and -20 dB isolation.
Abstract: In this letter, a planar microstrip crossover junction is presented. The conductor-backed coplanar waveguide (CB-CPW) structure with vias is employed as the core part of the crossover design. The dimensions of the CB-CPW crossover itself are 11.3 × 11.3 mm2. Two kinds of the transitions between the microstrip line (MSL) and the CB-CPW structure are merged into a double side print circuit board. This presented crossover junction has a bandwidth from 10 up to 6000 MHz for 20 dB return loss, 1 dB insertion loss and -20 dB isolation. Compared with the other designs, this planar crossover features wide bandwidth and compact configuration.
TL;DR: In this article, a fluidic microstrip bandstop filter with transmission properties that change in discrete states is described, where the frequency response of the filter changes in response to the changes in the length of the resonator stub.
Abstract: This letter describes a fluidic microstrip bandstop filter with transmission properties that change in discrete states. The filter consists of a liquid metal alloy - eutectic gallium indium (EGaIn) - as the conductive component in microfluidic channels. The fluidity of EGaIn allows the open stub resonator of the filter to change its length by flowing in response to an applied pressure. A series of posts in the channel defines the length of the stub filled by the metal and dictates the pressure needed for the liquid metal to flow and thereby extend the stub length. The frequency response of the filter changes in response to the changes in the length of the resonator stub. This approach is a simple method for creating tunable filters and impedance matching sections using soft materials that change dimensions in response to pressure.
TL;DR: In this article, a wideband branch-line couplers with arbitrary coupling levels are demonstrated, and a method is demonstrated that introduces intentional mismatch for a further enhancement in bandwidth.
Abstract: Wideband branch-line couplers with arbitrary coupling levels are demonstrated. By integrating single-section quarter-wave transformers at each port, wideband characteristic with excellent coupling flatness is achieved. Also, a method is demonstrated that introduces intentional mismatch for a further enhancement in bandwidth. Superior structural and design simplicity outperform previous wideband couplers. Branch-line couplers at 3 GHz are demonstrated experimentally that maintain the coupling level within 0.5 dB from the specified 10 dB in as much as a 50.9% bandwidth, with minimum return loss and isolation of 16.3 and 18.7 dB, respectively.
TL;DR: In this article, a nonlinear least squares problem involving eigenvalues of matrix pencils derived from the coupling matrix and reference zeros and poles of scattering parameters was proposed to synthesize coupled-resonator filters.
Abstract: This letter presents a novel technique for synthesis of coupled-resonator filters with inter-resonator couplings varying linearly with frequency. The values of non-zero elements of the coupling matrix are found by solving a nonlinear least squares problem involving eigenvalues of matrix pencils derived from the coupling matrix and reference zeros and poles of scattering parameters. The proposed method was verified by numerical tests carried out for various coupling schemes including triplets and quadruplets for which the frequency-dependent coupling was found to produce an extra zero.
TL;DR: In this article, a step group-delay phaser is proposed and demonstrated to eliminate the issue of frequency resolution limitation due to the dispersion spreading induced by conventional phasers, and the concept of real-time spectrum sniffing is introduced for cognitive radio systems.
Abstract: The concept of real-time spectrum sniffing - featuring a simple and low-cost circuit architecture with straightforward frequency scalability - is introduced for cognitive radio systems. A stepped group-delay phaser is proposed and demonstrated to eliminate the issue of frequency resolution limitation due to the dispersion spreading induced by conventional phasers.
TL;DR: In this paper, a single slotted circular patch resonator is proposed to design a dual-mode dual-band bandpass filter with input/output cross coupling, which exhibits a sharp out-of-band rejection skirt and good rejection between the dual passbands.
Abstract: A single slotted circular patch resonator is proposed in this letter to design a novel dual-mode dual-band bandpass filter. Four identical arc-oriented slots are first symmetrically etched into the circular patch resonator to move the TM01-like mode to a lower frequency. Together with the TM21-like mode, these two modes make up the second passband of the proposed filter. A pair of radial-oriented slots is then etched into the edge of the circular patch to split a pair of TM11-like degenerate modes, which forms the first dual-mode passband. Two high-impedance transmission lines are connected to the proposed resonator at a 90° angle to properly excite the four resonant modes described above. Finally, a filter with input/output cross coupling is designed, fabricated and tested to demonstrate the dual-mode dual-band filtering performance, which exhibits a sharp out-of-band rejection skirt and good rejection between the dual passbands.
TL;DR: In this paper, a microstrip ultra-wideband differential filter with narrow notched band based on the transversal signal-interference concept is presented, which is implemented by coupling with quarter wavelength shorted-line at input and output ports.
Abstract: A novel microstrip ultra-wideband (UWB) differential filter with narrow notched band based on the transversal signal- interference concept is presented. In order to enhance the interference immunity from undesired signals efficiently, the notched band is implemented by coupling with quarter wavelength shorted-line at input and output ports. By taking advantage of the bandgap characteristic of defected ground structure (DGS), a slot-line DGS is used for improving the common-mode rejection. In this work, at the center frequency of the notched band which is 2.45 GHz, about 7.3% bandwidth (2.35-2.53 GHz) is realized by full-wave simulator. Agreement between experiment and simulation is observed.
TL;DR: In this paper, a broadside-coupled microstrip-to-coplanar waveguide (CPW) transition and a pair of uniplanar microstripto-CPW transition are employed for ultra-wideband microwave circuits.
Abstract: The design of an ultra-wideband crossover for use in printed microwave circuits is presented. It employs a pair of broadside-coupled microstrip-to-coplanar waveguide (CPW) transitions, and a pair of uniplanar microstrip-to-CPW transitions. A lumped-element equivalent circuit is used to explain the operation of the proposed crossover. Its performance is evaluated via full-wave electromagnetic simulations and measurements. The designed device is constructed on a single substrate, and thus, it is fully compatible with microstrip-based microwave circuits. The crossover is shown to operate across the frequency band from 3.1 to 11 GHz with more than 15 dB of isolation, less than 1 dB of insertion loss, and less than 0.1 ns of deviation in the group delay.
TL;DR: In this article, a coupled-cavity bandpass filter with a four-pole generalized Chebyshev filter with three transmission zeros is proposed, where the frequency-dependent coupling was realized via a rectangular waveguide iris with an incomplete height conducting post.
Abstract: This letter presents an application of a recently developed coupling matrix synthesis technique to design of coupled-resonator filters with dispersive inter-resonator couplings. This technique is used to design a novel coupled-cavity bandpass filter. Measurements validate the design and confirm effectiveness of the synthesis method. The filter is a four-pole generalized Chebyshev filter with three transmission zeros. Resonators are arranged in a quadruplet configuration and employ a single dispersive cross coupling to produce an extra zero in comparison to classical approaches. Frequency-dependent coupling was realized via a rectangular waveguide iris with an incomplete height conducting post.
TL;DR: In this article, a micromachined 385 GHz rectangular waveguide cavity bandpass filter is presented, which is fabricated using deep reactive ion etching on silicon substrate, with sputtered gold inner surface metallization.
Abstract: A micromachined 385 GHz rectangular waveguide cavity bandpass filter is presented. The proposed filter is fabricated using deep reactive ion etching on silicon substrate, with sputtered gold inner surface metallization. The vector network analyzer measured results show the lowest insertion loss is about 2.7 dB with a 15 GHz bandwidth. Effects of micro-electro-mechanical systems process on the filter's performance are discussed in detail.
TL;DR: In this article, an ultra-wideband (UWB) bandpass filter with multiple notch bands is presented, which is achieved using a modified distributed highpass filter (HPF) and suppressing higher order harmonics of the HPF by realizing defected stepped impedance resonator.
Abstract: In this letter, an ultra-wideband (UWB) bandpasss filter with multiple notch bands is presented. The UWB bandpass characteristic is achieved using a modified distributed highpass filter (HPF) and suppressing higher order harmonics of the HPF by realizing defected stepped impedance resonator. The dual band notches at 5.75 and 8.05 GHz are obtained by embedding two open stubs on the main microstrip line. The in band and out of band performance obtained from fullwave electromagnetic simulation, equivalent circuit model and measurement are in good agreement.
TL;DR: In this article, a novel wideband microstrip band-pass filter is presented based on a quadruplemode ring resonator, which is developed by introducing a stepped-impedance one-wavelength ring resonators (SORR) into a step-impingance half-wvelength resonator (SHR) in order to suppress the harmonic responses of the filter for a wide stop-band.
Abstract: A novel wideband microstrip band-pass filter is presented in this letter based on a quadruple-mode ring resonator, which is developed by introducing a stepped-impedance one-wavelength ring resonator (SORR) into a stepped-impedance half-wavelength resonator (SHR). In order to suppress the harmonic responses of the filter for a wide stop-band, two band-stop sections with asymmetrical -type structure are introduced. A prototype filter having 49.3% of 1 dB and 57.9% of 3 dB fractional bandwidth is fabricated with advantages of high selectivity and high out-of-band rejection. In the pass-band, the return loss is larger than 18.8 dB and at the centre frequency insertion loss is 0.6 dB. The experiments are in good agreement with the simulations.
TL;DR: In this paper, a new technique to fabricate microwave circuits in paper substrates is proposed, which relies on a copper adhesive tape that is shaped by a photo-lithographic process and then transferred to the hosting substrate by means of a sacrificial layer.
Abstract: In this work, a new technique to fabricate microwave circuits in paper substrates is proposed. This technique relies on a copper adhesive tape that is shaped by a photo-lithographic process and then transferred to the hosting substrate by means of a sacrificial layer. Microstrip lines in paper substrates have been electromagnetically characterized accounting also for the adhesive layers. Experimental results show an insertion loss better than 0.6 dB/cm at 10 GHz.
TL;DR: In this paper, a balanced-to-balanced Gysel power divider (PD) is proposed for high-power applications, based on a half-mode substrate integrated waveguide (SIW) ring.
Abstract: A new balanced-to-balanced Gysel power divider (PD) is proposed for high-power applications, based on a half-mode substrate integrated waveguide (SIW) ring. The ring has a circumference of 2.5 λg, and one port is used for good isolation. The balanced-to-balanced component is easily designed by converting its single-ended counterpart. With the equivalent impedance defined by voltage and current of half-mode SIW, the initial geometry is quickly obtained. Good performance is achieved with our proposed PD, which has been demonstrated by its simulated and measured mixed-mode S-parameters.