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Showing papers on "Insertion loss published in 2007"


Journal ArticleDOI
TL;DR: In this paper, the trade-offs between resonantly enhanced group delay, device size, insertion loss and operational bandwidth are analyzed for various delay-line designs, and a large fractional group delay exceeding 10 bits is achieved for bit rates as high as 20 Gbps.
Abstract: On-chip optical buffers based on waveguide delay lines might have significant implications for the development of optical interconnects in computer systems. Silicon-on-insulator (SOI) submicrometre photonic wire waveguides are used, because they can provide strong light confinement at the diffraction limit, allowing dramatic scaling of device size. Here we report on-chip optical delay lines based on such waveguides that consist of up to 100 microring resonators cascaded in either coupled-resonator or all-pass filter (APF) configurations. On-chip group delays exceeding 500 ps are demonstrated in a device with a footprint below 0.09 mm2. The trade-offs between resonantly enhanced group delay, device size, insertion loss and operational bandwidth are analysed for various delay-line designs. A large fractional group delay exceeding 10 bits is achieved for bit rates as high as 20 Gbps. Measurements of system-level metrics as bit error rates for different bit rates demonstrate error-free operation up to 5 Gbps.

1,161 citations


Journal ArticleDOI
TL;DR: Ultra-compact 5(th) order ring resonator optical filters based on submicron silicon photonic wires are demonstrated, all within a footprint of 0.0007mm(2) on a silicon chip.
Abstract: Ultra-compact 5(th) order ring resonator optical filters based on submicron silicon photonic wires are demonstrated. Out-of-band rejection ratio of 40dB, 1dB flat-top pass band of 310GHz with ripples smaller than 0.4dB, and insertion loss of only (1.8+/-0.5)dB at the center of the pass band are realized simultaneously, all within a footprint of 0.0007mm(2) on a silicon chip.

453 citations


Journal ArticleDOI
TL;DR: In this paper, two 4-bit active phase shifters integrated with all digital control circuitry in 0.13mum RF CMOS technology are developed for X- and Ku-band (8-18 GHz) and K-band(18-26 GHz) phased arrays, respectively.
Abstract: Two 4-bit active phase shifters integrated with all digital control circuitry in 0.13-mum RF CMOS technology are developed for X- and Ku-band (8-18 GHz) and K-band (18-26 GHz) phased arrays, respectively. The active digital phase shifters synthesize the required phase using a phase interpolation process by adding quadrature-phased input signals. The designs are based on a resonance-based quadrature all-pass filter for quadrature signaling with minimum loss and wide operation bandwidth. Both phase shifters can change phases with less than about 2 dB of RMS amplitude imbalance for all phase states through an associated DAC control. For the X- and Ku-band phase shifter, the RMS phase error is less than 10o over the entire 5-18 GHz range. The average insertion loss ranges from to at 5-20 GHz. The input for all 4-bit phase states is typically at -5.4 plusmn1.3 GHz in the X- and Ku-band phase shifter. The K-band phase shifter exhibits 6.5-13 of RMS phase error at 15-26 GHz. The average insertion loss is from 4.6 to at 15-26 GHz. The input of the K-band phase shifter is at 24 GHz. For both phase shifters, the core size excluding all the pads and the output 50 Omega matching circuits, inserted for measurement purpose only, is very small, 0.33times0.43 mm2 . The total current consumption is 5.8 mA in the X- and Ku-band phase shifter and 7.8 mA in the K-band phase shifter, from a 1.5 V supply voltage.

374 citations


Journal ArticleDOI
TL;DR: In this article, the design and experiment of the half mode substrate integrated waveguide (HMSIW) bandpass filters are presented, and the measured results are in good agreement with the simulated results.
Abstract: This letter presents the design and experiment of the half mode substrate integrated waveguide (HMSIW) bandpass filters. Three-pole and five-pole HMSIW filters are simulated by using CST software and fabricated with a single layer standard printed circuit board process. Different external-coupling approaches are adopted in the design of the two filters. The measured results are in good agreement with the simulated results. Low insertion loss and good selectivity are achieved

272 citations


Journal ArticleDOI
TL;DR: In this paper, a stub-loaded multiple-mode resonator (MMR) is proposed for ultra wideband bandpass filtering, which is formed by loading three open-ended stubs in shunt to a simple stepped-impedance resonator in center and two symmetrical locations.
Abstract: A compact microstrip-line ultra-wideband (UWB) bandpass filter (BPF) using the proposed stub-loaded multiple-mode resonator (MMR) is presented. This MMR is formed by loading three open-ended stubs in shunt to a simple stepped-impedance resonator in center and two symmetrical locations, respectively. By properly adjusting the lengths of these stubs, the first four resonant modes of this MMR can be evenly allocated within the 3.1-to-10.6 GHz UWB band while the fifth resonant frequency is raised above 15.0GHz. It results in the formulation of a novel UWB BPF with compact-size and widened upper-stopband by incorporating this MMR with two interdigital parallel-coupled feed lines. Simulated and measured results are found in good agreement with each other, showing improved UWB bandpass behaviors with the insertion loss lower than 0.8dB, return loss higher than 14.3dB, and maximum group delay variation less than 0.64ns in the realized UWB passband

264 citations


Journal ArticleDOI
TL;DR: A 50-channel high-resolution arrayed waveguide grating microspectrometer with a 0.2 nm channel spacing on a silicon-on-insulator (SOI) platform with high channel density and spectral resolution is demonstrated.
Abstract: We demonstrate a 50-channel high-resolution arrayed waveguide grating microspectrometer with a 0.2 nm channel spacing on a silicon-on-insulator (SOI) platform. The chip size is 8 mm x 8 mm. High channel density and spectral resolution are achieved using high aspect ratio 0.6 mum x 1.5 mum waveguide apertures to inject the light into the input combiner and to intercept different spectral channels at the output combiner focal region. The measured crosstalk is <-10 dB, the 3 dB channel bandwidth is 0.15 nm, and the insertion loss is -17 dB near the central wavelength of lambda = 1.545 mum.

261 citations


Journal ArticleDOI
TL;DR: This is the first demonstration of a functional polarization-diversity circuit implemented in SOI nanophotonic waveguides, including interfaces to single-mode fiber, and it is shown that polarization insensitive operation is achieved through a special polarization diversity approach.
Abstract: We present a wavelength duplexer based on a compact arrayed waveguide grating (AWG) in silicon-on-insulator photonic wire waveguides. Polarization insensitive operation is achieved through a special polarization diversity approach in which we use 2-D grating fiber couplers as integrated polarization splitters. To mitigate the effects of process variations, we propagated both polarizations in opposite directions through the same AWG with a mere 600x350microm(2) footprint. This resulted in an on-chip insertion loss between -2.1dB and -6.9dB, crosstalk of -15dB, and only 0.66dB polarization dependent loss. This is the first demonstration of a functional polarization-diversity circuit implemented in SOI nanophotonic waveguides, including interfaces to single-mode fiber.

245 citations


Journal ArticleDOI
TL;DR: In this article, a new class of single-chip multiple-frequency (up to 236 MHz) filters that are based on low motional resistance contour-mode aluminum nitride piezoelectric micromechanical resonators is presented.
Abstract: This paper reports experimental results on a new class of single-chip multiple-frequency (up to 236 MHz) filters that are based on low motional resistance contour-mode aluminum nitride piezoelectric micromechanical resonators. Rectangular plates and rings are made out of an aluminum nitride layer sandwiched between a bottom platinum electrode and a top aluminum electrode. For the first time, these devices have been electrically cascaded to yield high performance, low insertion loss (as low as 4 dB at 93MHz), and large rejection (27 dB at 236 MHz) micromechanical bandpass filters. This novel technology could revolutionize wireless communication systems by allowing cofabrication of multiple frequency filters on the same chip, potentially reducing form factors and manufacturing costs. In addition, these filters require terminations (1 kOmega termination is used at 236 MHz) that can be realized with on-chip inductors and capacitors, enabling their direct interface with standard 50-Omega systems

217 citations


Journal ArticleDOI
TL;DR: In this paper, a half mode substrate integrated waveguide (HMSIW) 3-dB coupler is proposed, which keeps the good performance of the SIW coupler with nearly a half reduction in size.
Abstract: In the microwave band, substrate integrated waveguide (SIW) couplers take the advantages of low profile, low insertion loss, low interference etc., but suffer from the big size. In this letter, a novel half mode substrate integrated waveguide (HMSIW) 3-dB coupler is proposed, which keeps the good performance of the SIW coupler with nearly a half reduction in size. Simulated results are in agreement with the measured data

214 citations


Journal ArticleDOI
TL;DR: In this paper, a planar diplexer based on the complementary response characters of substrate integrated waveguide (SIW) dual-mode filters with circular and elliptic cavities is proposed.
Abstract: A novel high-performance millimeter-wave planar diplexer is developed based on the complementary characters of substrate integrated waveguide (SIW) dual-mode filters with circular and elliptic cavities by making the tradeoff between the isolation, insertion loss, and selectivity. The responses of the dual-mode SIW circular and elliptic cavities are first investigated. It can be found that the upper side response of the circular cavity and the lower side response of the elliptic cavity are very steep. The diplexers with high isolation performance are then designed based on the complementary response characters of circular and elliptic cavities. A diplexer with two dual-mode SIW circular and elliptic cavities is designed and fabricated with a normal printed circuit board process. The measured insertion losses are 1.95 and 2.09 dB in the upper and lower passbands centered at 26 and 25 GHz with the fractional bandwidths of 5.2% and 5.4%. The isolation is lower than - 50dB

205 citations


Journal ArticleDOI
TL;DR: In this paper, an EBG-embedded multiple-mode resonator (MMR) is proposed to constitute an upper-stopband-improved and size-miniaturized ultra wideband (UWB) bandpass filter (BPF).
Abstract: An electromagnetic bandgap (EBG) embedded multiple-mode resonator (MMR) is proposed to constitute an upper-stopband-improved and size-miniaturized ultra-wideband (UWB) bandpass filter (BPF). This EBG-embedded MMR is studied to relocate its first three resonant modes within the 3.1-10.6GHz passband, whereas placing its 4th resonant mode at the coupling transmission zero of interdigital coupled-lines that drive this MMR at two sides. Meanwhile, the fifth resonant mode is rejected by virtue of the bandstop behavior of the EBG itself. Thus, a modified UWB BPF with widened upper-stopband, sharpened upper rejection skirt and lowered loss in the passband is finally constituted, designed and fabricated. The measured results demonstrate that the insertion loss is lower than 1.0 dB in the passband (4.0-10.6GHz) and higher than 15.0dB in the upper-stopband (12.0 to 20.0GHz) while the group delay variation in the passband is less than 0.2ns

Journal ArticleDOI
TL;DR: In this paper, the design of a compact out-of-phase uniplanar power divider operating over an ultra wide frequency band is presented, where a T-junction formed by a slotline and a microstrip line accompanied by wideband microstrip to slotline transitions is employed.
Abstract: The design of a compact out-of-phase uniplanar power divider operating over an ultra wide frequency band is presented. To achieve an out-of-phase signal division over a large frequency range, a T-junction formed by a slotline and a microstrip line accompanied by wideband microstrip to slotline transitions is employed. The simulated and experimental results of the developed divider show a low insertion loss and good return loss performance of the three ports across the band 3.1-10.6 GHz

Journal ArticleDOI
TL;DR: A three dimensional fan-out device has been fabricated using ultrafast laser inscription that allows each core of a multicore fibre to be addressed individually by a single mode fiber held in an FVA.
Abstract: A fan-out device has been fabricated using ultrafast-laser waveguide-inscription that enables each core of a multicore optical fiber (MCF) to be addressed by a single mode fiber held in a fiber V-groove array (FVA). By utilizing the unique three-dimensional fabrication capability of this technique we demonstrate coupling between an FVA consisting of a one-dimensional array of fibers and an MCF consisting of a two-dimensional array of cores. When coupled to all cores of the MCF simultaneously, the average insertion loss per core was 5.0 dB in the 1.55 mum spectral region. Furthermore, the fan-out exhibited low cross-talk and low polarization dependent loss.

Journal ArticleDOI
TL;DR: In this paper, a pseudo-interdigital stepped impedance resonators (PI-SIRs) are used to design the bandpass filter (BPF) with dual-band response.
Abstract: In this letter, pseudo-interdigital stepped impedance resonators (PI-SIRs) are used to design the bandpass filter (BPF) with dual-band response. By tuning the impedance ratio (K) and physical length of SIRs, the BPF has good dual-passband performances at 2.4/5.2GHz and high isolation between the two passbands. It is shown that the dual-band BPF has a smaller area and lower insertion loss in comparison of previous works. Good agreement is shown between the full-wave electromagnetic simulation and the measurement

Journal ArticleDOI
TL;DR: In this article, a method with clear guidelines is presented to design compact planar phase shifters with ultra wideband (UWB) characteristics, which exploits broadside coupling between top and bottom elliptical microstrip patches via an elliptical slot located in the mid layer, which forms the ground plane.
Abstract: A method with clear guidelines is presented to design compact planar phase shifters with ultra-wideband (UWB) characteristics. The proposed method exploits broadside coupling between top and bottom elliptical microstrip patches via an elliptical slot located in the mid layer, which forms the ground plane. A theoretical model is used to analyze performance of the proposed devices. The model shows that it is possible to design high-performance UWB phase shifters for the 25deg-48deg range using the proposed structure. The method is used to design 30deg and 45deg phase shifters that have compact size, i.e., 2.5 cm times 2 cm. The simulated and measured results show that the designed phase shifters achieve better than plusmn3deg differential phase stability, less than 1-dB insertion loss, and better than 10-dB return loss across the UWB, i.e., 3.1-10.6 GHz.

Journal ArticleDOI
TL;DR: In this article, a frequency selective surface (FSS) which exploits the dielectric anisotropy of liquid crystals to generate an electronically tunable bandpass filter response at D Band (110-170 GHz) is presented.
Abstract: A frequency selective surface (FSS) which exploits the dielectric anisotropy of liquid crystals to generate an electronically tunable bandpass filter response at D Band (110-170 GHz) is presented. The device consists of two printed arrays of slot elements which are separated by a 130-mum thick layer of liquid crystals. A 3% shift in the filter passband occurs when the substrate permittivity is increased by applying a control signal of 10 V. Measured results show that the insertion loss increases from -3.7 dB to -10.4 dB at resonance (134 GHz), thus demonstrating the potential to create a FSS which can be switched between a transmitting and a reflecting structure.

Journal ArticleDOI
TL;DR: The analysis shows that a series-only architecture using the customized transistor layout achieves better insertion loss and reasonable isolation, and a double-well body-floating technique is proposed and its effects are discussed.
Abstract: This paper presents the comprehensive considerations of CMOS transmit/receive (T/R) switch design towards ultra-wideband and over 15-GHz frequencies. Techniques for minimizing parasitics and increasing linearity are discussed. A customized transistor layout is proposed for T/R switch design and its effects on insertion loss and isolation are studied. The analysis shows that a series-only architecture using the customized transistor layout achieves better insertion loss and reasonable isolation. A double-well body-floating technique is proposed and its effects are discussed. A differential switch architecture without shunt arms is designed and verified by experimental results. Fabricated in 0.13-mum triple-well CMOS, the T/R switch exhibits less than 2 dB insertion loss and higher than 21 dB isolation up to 20 GHz. With resistive body floating and differential architecture, the high linearity is of ultra-wideband characteristic, more than 30-dBm power 1-dB compression point (P1dB) is obtained up to 20 GHz in only 0.03 mm2 active die area.

Journal ArticleDOI
Y. Jin1, Cam Nguyen1
TL;DR: In this paper, a fully integrated ultra-broadband transmit/receive (T/R) switch was developed using nMOS transistors with a deep n-well in a standard 0.18mum CMOS process, and demonstrates unprecedented insertion loss, isolation, power handling, and linearity.
Abstract: A fully integrated ultra-broadband transmit/receive (T/R) switch has been developed using nMOS transistors with a deep n-well in a standard 0.18-mum CMOS process, and demonstrates unprecedented insertion loss, isolation, power handling, and linearity. The new CMOS T/R switch exploits patterned-ground-shield on-chip inductors together with MOSFET's parasitic capacitances to synthesize artificial transmission lines, which result in low insertion loss over an extremely wide bandwidth. Negative bias to the bulk or positive bias to the drain of the MOSFET devices with floating bulk is used to reduce effects of the parasitic diodes, leading to enhanced linearity and power handling for the switch. Within dc-10, 10-18, and 18-20 GHz, the developed CMOS T/R switch exhibits insertion loss of less than 0.7, 1.0, and 2.5 dB and isolation between 32-60, 25-32, and 25-27 dB, respectively. The measured 1-dB power compression point and input third-order intercept point reach as high as 26.2 and 41 dBm, respectively. The new CMOS T/R switch has a die area of only 230 mumtimes250 mum. The achieved ultra-broadband performance and high power-handling capability, approaching those achieved in GaAs-based T/R switches, along with the full-integration ability confirm the usefulness of switches in CMOS technology, and demonstrate their great potential for many broadband CMOS radar and communication applications

Journal ArticleDOI
TL;DR: In this article, a compact slow-wave microstrip branch-line coupler is presented, which not only reduces the occupied area to 28% of the conventional branch line coupler at 2.0 GHz, but also has high second harmonic suppression performance.
Abstract: One compact slow-wave microstrip branch-line coupler is presented. The new structure not only effectively reduces the occupied area to 28% of the conventional branch-line coupler at 2.0 GHz, but also has high second harmonic suppression performance. The measured results indicate a bandwidth of more than 200 MHz has been achieved while the phase difference between S21 and S31 is within 90deg plusmn 1deg. Furthermore, the measured insertion loss is comparable to that of a conventional branch-line coupler. The new coupler can be easily implemented by using the standard printed-circuit-board etching processes and is very useful for wireless communication systems.

Journal ArticleDOI
TL;DR: In this paper, a modification of the Wilkinson power divider is presented that eases planar implementation while maintaining performance, by adding transmission lines between the resistor and the quarter-wave transformers of the traditional design, a range of valid solutions exists that meet the conditions of being reciprocal, isolated between the output ports and matched at all ports.
Abstract: A modification of the Wilkinson power divider is presented that eases planar implementation while maintaining performance. By adding transmission lines between the resistor and the quarter-wave transformers of the traditional design, a range of valid solutions exists that meet the conditions of being reciprocal, isolated between the output ports, and matched at all ports. The proposed design is particularly useful at millimeter-wave frequencies where reduced physical dimensions make a circuit configuration suitable for low-cost package-level implementation difficult using traditional methods. Two frequency bands are demonstrated. At V-band, the circuit gives 0.3-dB excess insertion loss, 19-dB isolation, and 50% bandwidth. At the W-band, the circuit gives 0.75-dB excess insertion loss, 24-dB isolation, and 39% bandwidth.

Journal ArticleDOI
TL;DR: In this article, a Hilbert curve ring (HCR) fractaldefected ground structure (DGS) and its equivalent circuit are investigated and an improved HCR DGS cell model with open stubs loaded on the conductor line is presented to improve the out-band suppression.
Abstract: LOWPASSFILTERDESIGNOFHILBERTCURVERINGDEFECTEDGROUNDSTRUCTUREJ.Chen,Z.-B.Weng,Y.-C.Jiao,andF.-S.ZhangNational Key Laboratory of Antennas and Microwave TechnologyXidian UniversityXi’an 710071,ChinaAbstract—In this paper,a novel Hilbert curve ring (HCR) fractaldefected ground structure (DGS) and its equivalent circuit areinvestigated. Furthermore,an improved HCR DGS cell model withopen stubs loaded on the conductor line is then presented to improvethe out-band suppression. By employing three cascaded improvedHCR DGS cells,an L-band microstrip low-pass is designed andfabricated. This lowpass filter achieves a quite steep rejection property;a low in-band insertion loss of below 0.5dB and a high out-bandsuppression of more than 33dB.1. INTRODUCTIONRecently,there has been an increasing interest in the applicationsof defected ground structure (DGS) in microwave and millimeter-wave applications [1–3]. The DGS of the microstrip line employsan intentional defect on the ground and it provides band rejectioncharacteristic from the resonance property. The applications of theDGS are developed in divider,filter,and amplifier circuits. Thedefect of the conventional DGS is with the dumbbell shape or therectangle shape,these conventional DGSs,however,have a flat slopeof their rejection characteristic. To fabricate a lowpass filter with steeprejection property,many these DGSs are needed to be cascaded,whichalso means higher in-band insertion and larger size.Different from Euclidean geometries,fractal geometries have twocommon properties,space-filling and self-similarity. It has been shownthat the self-similarity property of fractal shapes can be successfullyapplied to the design of multi-band fractal antennas,such as theSierpinski gasket antenna [4],while the space-filling property of fractalscan be utilized to reduce antenna size [5,6].

Journal ArticleDOI
TL;DR: In this paper, an impedance-transforming quadrature coupler with equalized series-resonated varactors is used to increase the maximal relative phase shift for a given varactor with a limited capacitance range.
Abstract: reflection-type phase shifter with constant insertion loss over a wide relative phase-shift range is presented. This important feature is attributed to the salient integration of an impedance-transforming quadrature coupler with equalized series-resonated varactors. The impedance-transforming quadrature coupler is used to increase the maximal relative phase shift for a given varactor with a limited capacitance range. When the phase is tuned, the typical large insertion-loss variation of the phase shifter due to the varactor parasitic effect is minimized by shunting the series-resonated varactor with a resistor Rp. A set of closed-form equations for predicting the relative phase shift, insertion loss, and insertion-loss variation with respect to the quadrature coupler and varactor parameters is derived. Three phase shifters were implemented with a silicon varactor of a restricted capacitance range of Cv,min = 1.4 pF and Cv,max = 8 pF, wherein the parasitic resistance is close to 2 Omega. The measured insertion-loss variation is 0.1 dB over the relative phase-shift tuning range of 237deg at 2 GHz and the return losses are better than 20 dB, excellently agreeing with the theoretical and simulated results.

Journal ArticleDOI
Wang Wen1, He Shitang1, Li Shunzhou1, Liu Minghua1, Pan Yong 
TL;DR: In this article, a 300MHz surface acoustic wave (SAW) gas sensor coated molecularly imprinted polymer incorporating a novel SAW oscillator with high frequency stability was fabricated as the oscillator element.
Abstract: This paper presents a 300 MHz surface acoustic wave (SAW) gas sensor coated molecularly imprinted polymer incorporating a novel SAW oscillator with high frequency stability. A SAW delay line on ST-X quartz substrate with low insertion loss (less than 12 dB) and single mode selection capability was fabricated as the oscillator element. Electrode width control single phase unidirectional transducer (EWC/SPUDT) configuration and comb transducer were used to structure the SAW device to minimize the insertion loss and accomplish the single mode selection, respectively. Prior to fabrication, coupling of modes (COM) simulation was performed to predict device performance. The measured frequency response S 12 showed a good agreement with simulated results. The effect of oscillator circuit system temperature shift upon frequency stability of the fabricated oscillator was studied in detail. Typical short-term frequency stability (1 h) of ∼0.06 ppm (∼20 Hz) for the fabricated 300 MHz SAW oscillator was observed in a laboratory environment with temperature control. The oscillator was successfully applied to gas sensor coated 10 nm molecularly imprinted polymer (MIP) as sensor material for dimethyl-methyl-phosphonate (DMMP), and the MIP was prepared using o -phenylenediamine ( o -PD) as a functional monomer, Sarin acid as a molecular template and co-polymerized using cyclic voltammetry (CV). The sensitivity for DMMP concentrations detection in a range of 1–100 mg/m 3 was evaluated as ∼96 Hz/mg/m 3 , and the threshold detection limit was up to 0.5 mg/m 3 .

Journal ArticleDOI
TL;DR: In this paper, the authors derived closed-form expressions for the nonlinearity in the optical I/Q modulator, represented by two-tone intermodulation products as a function of the bias point and modulation index.
Abstract: In this letter, we conduct analysis on the optimum design for RF-to-optical up-converter in coherent optical OFDM systems using an optical I/Q modulator. We first derive closed-form expressions for the nonlinearity in the optical I/Q modulator, represented by two-tone intermodulation products as a function of the bias point and modulation index. Additionally, we perform a numerical simulation to identify Q-penalty and the excess modulation insertion loss under various transmitter conditions. We find that in contrast to the direct-detected system, the optimal modulator bias point for the coherent system is pi, where the Q-penalty and excess loss are minimized

Journal ArticleDOI
TL;DR: In this article, a surface acoustic wave device which can prevent a breakage of electrodes and electrical breaks, decrease an insertion loss of elements, and enhance a Q-factor of resonators is provided.
Abstract: There is provided a surface acoustic wave device which can prevent a breakage of electrodes and electrical breaks, decrease an insertion loss of elements, and enhance a Q-factor of resonators. Interdigital electrode sections and each have a laminated structure of a base layer made of TiN (titanium nitride) or TiOxNy and a main electrode layer deposited to come in contact with an upper surface of the base layer. The main electrode layer is deposited such that a {111} plane as a closest-packed plane of the main electrode layer has a constant gradient with respect to a surface of a substrate, and thus electromigration or stress migration can be suppressed in the interdigital electrode sections.

Journal ArticleDOI
TL;DR: In this article, a planar ultra wideband bandpass filter is proposed, where three interdigital edge coupled microstrip lines are used for coupling enhancement and a stepped impedance open stub is used for realizing transmission zeros simultaneously in upper and lower stop bands as well as impedance matching in ultra wide pass band.
Abstract: The design and implementation of a planar ultra-wideband (UWB) bandpass filter are presented. Three interdigital edge coupled microstrip lines are used for coupling enhancement. A stepped impedance open stub is used for realizing transmission zeros simultaneously in upper and lower stop bands as well as impedance matching in ultra-wide pass band. A pass band from 3.1-10.6 GHz is achieved with an insertion loss of 0.5 dB, a return loss of about 18 dB, a sharp out-of-band-rejection, and a low group delay of only 0.21ns. Single- and double-section filters are realized to meet the UWB mask requirement. The design of the filter is simple, and it shows good frequency response.

Journal ArticleDOI
TL;DR: A fully integrated single-pole-double-throw transmit/receive switch has been designed and fabricated in standard bulk 90-nm complementary metaloxide semiconductor (CMOS) technology.
Abstract: A fully integrated single-pole-double-throw transmit/receive switch has been designed and fabricated in standard bulk 90-nm complementary metal-oxide semiconductor (CMOS) technology. Traveling wave concept was used to minimize the insertion loss at higher frequency and widen the operating bandwidth. The switch exhibits a measured insertion loss of 2.7 -dB, an input 1-dB compression point (input P1 dB) of 15 dBm, and a 29-dB isolation at the center frequency of 77 GHz. The total chip size is only 0.57 times 0.42 mm 2 including all testing pads. To our knowledge, this is the first CMOS switch demonstrated beyond 50 GHz, and the performances rival those monolithic microwave integrated circuit switches using standard GaAs PHEMTs

Journal ArticleDOI
TL;DR: In this article, a planar power divider with an effective technique for nth harmonic suppression is proposed to reduce the length of a quarter-wave line over 30% as compared to the conventional divider.
Abstract: This letter presents a planar power divider with an effective technique for nth harmonics suppression. The proposed technique served by a microstrip electromagnetic bandgap cell is used to suppress the nth harmonics and reduce the length of a quarter-wave line over 30% as compared to the conventional divider. The planar structure enables an easy circuit design in printed circuit boards. From the measured results, a 32.5 dB suppression for the third harmonic and a 12 dB suppression for the fifth harmonic is obtained while maintaining the characteristics of a conventional Wilkinson power divider. It is able to achieve less than 3.4 0.1 dB of the two equivalent insertion losses, less than 23dB of the return loss, and better than 25dB of isolation at 2.4GHz.

Journal ArticleDOI
TL;DR: In this article, the authors presented a 24 GHz four-way and two-way miniature Wilkinson power dividers (PDs) in a standard CMOS technology, and the chip area was significantly reduced using a lumped-element design.
Abstract: This letter presents 24 GHz four-way and two-way miniature Wilkinson power dividers (PDs) in a standard CMOS technology. The chip area is significantly reduced using a lumped-element design, and the effective areas of four-way and two-way Wilkinson dividers are 0.33 times 0.33 mm2 and 0.12 times 0.29 mm2, respectively. The four-way Wilkinson divider results in an insertion loss 24.7 dB from 22 to 26 GHz. The two-way Wilkinson divider results in an insertion loss 14.8 dB from 22 to 26 GHz. To the author's knowledge, this is the first demonstration of 24 GHz four-way Wilkinson PD in a standard CMOS technology.

Journal ArticleDOI
TL;DR: In this paper, a surface micromachined RF microelectromechanical switch that uses piezoelectric actuators is presented, which exhibits better than 20dB isolation from dc up to 65 GHz and as large as 70 dB below 1 GHz.
Abstract: This paper presents results on a surface micromachined RF microelectromechanical switch that uses piezoelectric actuators. The switch uses solution chemistry-derived lead zirconate titanate thin films spun deposited onto a high-resistivity silicon substrate with coplanar waveguide transmission lines. Actuation voltages, applied via circuits independent of the RF circuitry, average less than 10 V, with switch operation demonstrated as low as 2 V. The series switch exhibits better than 20-dB isolation from dc up to 65 GHz and as large as 70 dB below 1 GHz. In the closed state, the switch has an insertion loss less than 1 dB up to 40 GHz, limited in this demonstration by substrate losses from the elastic layer used to stress control the piezoelectric actuators. Switching speeds for the different designs are in the range of 40-60 ms. Thermal sensitivity measurements show no change in isolation observed for temperatures up to 125degC. However, an increase in actuation voltage is required at elevated temperatures.