scispace - formally typeset
Search or ask a question

Showing papers in "IEEE Microwave and Wireless Components Letters in 2004"


Journal ArticleDOI
TL;DR: In this article, a super-compact stopband microstrip structure is proposed, where the frequency gap is produced by an array of complementary split ring resonators (CSRRs), a concept proposed for the first time on the ground plane.
Abstract: In this letter a super-compact stopband microstrip structure is proposed. The frequency gap is produced by an array of complementary split ring resonators (CSRRs)-a concept proposed here for the first time-etched on the ground plane. This behavior is interpreted as due to the presence of a negative effective dielectric permittivity in the vicinity of resonance. The resulting device produces a deep rejection frequency band with sharp cutoff, and a pass band that exhibits very low losses and good matching. Due to the sub-lambda operation of CSRRs, the electrical size of the device is very small.

703 citations


Journal ArticleDOI
TL;DR: By etching longitudinal slots on the top metallic surface of the substrate integrated waveguide (SIW), an integrated slot-array antenna is proposed in this article, which takes the advantage of small size, low profile, and low cost, etc.
Abstract: By etching longitudinal slots on the top metallic surface of the substrate integrated waveguide (SIW), an integrated slot-array antenna is proposed in this letter. The whole antenna and feeding system are fabricated on a single substrate, which takes the advantage of small size, low profile, and low cost, etc. The design process and experimental results of a four-by-four SIW slot array antenna at X-band are presented.

498 citations


Journal ArticleDOI
TL;DR: In this article, the dispersion diagram of the composite right/left-handed transmission line (CRLH) is obtained analytically based on the Bloch-Floquet theory, and the unique phenomenon of infinite guided-wavelength propagation, with nonzero group velocity at a nonzero frequency, is explained.
Abstract: The composite right/left-handed (CRLH) transmission line (TL) is presented as a general TL possessing both left-handed (LH) and right-handed (RH) natures. The dispersion diagram of the two-dimensional (2-D) CRLH-TL is obtained analytically based on the Bloch-Floquet theory, and the unique phenomenon of infinite guided-wavelength propagation, with nonzero group velocity at a nonzero frequency, is explained. It is shown analytically that when the CRLH TL is "balanced", two eigenfrequencies at the /spl Gamma/ point (/spl beta/=0) of the Brillouin zone (BZ) degenerate at /spl omega//sub /spl Gamma// and a seamless transition from the LH to the RH modes without a bandgap can be achieved. In addition, these phenomena are demonstrated experimentally in the case of a CRLH microstrip line.

380 citations


Journal ArticleDOI
TL;DR: In this article, a reconfigurable microstrip antenna with switchable polarization sense is proposed, consisting of a corner-truncated square radiating patch, four small triangular conductors, and a microstrip line feed.
Abstract: A novel reconfigurable microstrip antenna with switchable polarization sense is proposed. The proposed antenna has a simple structure, consisting of a corner-truncated square radiating patch, four small triangular conductors, and a microstrip line feed. Using independently biased PIN diodes on the patch, it can produce linear polarization, or left- or right-hand circular polarization according to bias voltages. From the measured results, low cross-polarization levels when operated in the linear state and good axial ratios in the circular state are observed.

294 citations


Journal ArticleDOI
TL;DR: In this paper, split ring resonators (SRRs) are used to suppress spurious passband suppression in microstrip coupled line band pass filters by means of split-ring resonators.
Abstract: In this letter, spurious passband suppression in microstrip coupled line band pass filters by means of split ring resonators (SRRs) is demonstrated for the first time. By etching SRRs in the upper substrate side, in close proximity to conductor strip, strong magnetic coupling between line and rings arises at the resonant frequency of SRRs. This inhibits signal propagation in the vicinity of that frequency, allowing the rejection of undesired passbands by properly tuning SRRs. To test this novel technique, we have designed and fabricated two different SSRs-based filters. In one case, the rings have been designed to suppress only the first spurious band, and SRRs have been etched at both sides of the 50-/spl Omega/ access lines. For the other prototype, SRRs have been etched on the active device region (i.e., surrounding the parallel coupled lines) and have been tuned to eliminate the first and second undesired bands. The measured frequency responses for these devices confirm the efficiency of this technique to suppress frequency parasitics, with rejection levels near 40 dBs, leaving the passband unaltered. Since SRRs are small particles (with sub-wavelength dimensions at the resonant frequency), this approach does not add extra area to the final layouts. Moreover, the conventional design methodology of the filters holds.

198 citations


Journal ArticleDOI
TL;DR: In this article, an experimental single-layer active microwave absorber is described, where the conventional resistive layer is replaced by an active frequency selective surface (FSS) controlled by pin diodes.
Abstract: An experimental single-layer active microwave absorber in described. The absorber is a planar structure based upon the topology of a Salisbury screen, but in which the conventional resistive layer is replaced by an active frequency selective surface (FSS) controlled by pin diodes. The resulting structure has superior reflectivity-bandwidth characteristics compared to conventional passive absorbers of corresponding thickness. Measured data are presented and show that the reflectivity response of the absorber can be controlled over the frequency band from 9 to 13 GHz.

196 citations


Journal ArticleDOI
TL;DR: In this paper, a new idea of increasing operational bandwidth of a compact planar inverted F antenna (PIFA) by introducing open-end slots in the ground plane under the radiating patch is described.
Abstract: This letter describes a new idea of increasing operational bandwidth of a compact planar inverted F antenna (PIFA) by introducing open-end slots in the ground plane under the radiating patch. The slots are not in the way of active modules of a wireless transceiver and thus the proposed antenna size reduction method is attractive from the point of view of practical implementation.

196 citations


Journal ArticleDOI
TL;DR: In this paper, a Planar Inverted-F Antenna (PIFA) is proposed for cellular telephone applications. But the design of a compact PIFA is not discussed.
Abstract: This letter presents the design of a compact Planar Inverted-F Antenna (PIFA) suitable for cellular telephone applications. The quarter-wavelength antenna combines the use of a slot, shorted parasitic patches and capacitive loads to achieve multiband operation. The commercial electromagnetic software IE3D is used to design and optimize the structure. The resulting antenna can operate from 880 to 960 MHz and 1710 to 2170 MHz covering GSM, DCS, PCS, and UMTS standards with a VSWR better than 2.5. Good agreement is found between simulated and measured results.

195 citations


Journal ArticleDOI
TL;DR: In this paper, the authors proposed a new simplified Volterra series based model for RF power amplifiers by employing a "near-diagonality" pruning algorithm to remove the coefficients which are very small, or else not sensitive to the output error.
Abstract: Behavioral modeling techniques provide a convenient and efficient means to predict system-level performance without the computational complexity of full circuit simulation or physics-level analysis of nonlinear systems, thereby significantly speeding up the analysis process. General Volterra series based models have been successfully applied for radio frequency (RF) power amplifier (PA) behavioral modeling, but their high complexity tends to limit their applications to "weakly" nonlinear systems. To model a PA with strong nonlinearities and long memory effects, for example, the general Volterra model involves a great number of coefficients. In this letter, we propose a new simplified Volterra series based model for RF power amplifiers by employing a "near-diagonality" pruning algorithm to remove the coefficients which are very small, or else not sensitive to the output error, therefore dramatically reducing the complexity of the behavioral model.

185 citations


Journal ArticleDOI
TL;DR: In this article, a metamaterial surface composed of a periodic arrangement of Hilbert curve inclusions above a conducting ground plane is analyzed numerically and is shown to possess the properties of a high impedance surface by investigating the phase and magnitude of the reflection coefficient, /spl Gamma/, for a plane wave of normal incidence.
Abstract: A metamaterial surface, composed of a periodic arrangement of Hilbert Curve inclusions above a conducting ground plane, is analyzed numerically and is shown to possess the properties of a high impedance surface by investigating the phase and magnitude of the reflection coefficient, /spl Gamma/, for a plane wave of normal incidence. A parametric study is presented with respect to the iteration order of the Hilbert curve, the surface height above the ground plane, and the separation distance between the neighboring Hilbert elements within the surface array.

182 citations


Journal ArticleDOI
TL;DR: In this article, a defected ground structure (DGS) is applied to design a compact microstrip rat-race hybrid coupler, which can achieve both a significant reduction of size and harmonic signal.
Abstract: In this letter, a defected ground structure (DGS) is applied to design a compact microstrip rat-race hybrid coupler. The proposed structure can achieve both a significant reduction of size and harmonic signal. By embedding the DGS section, it is observed that the resonant frequency of the hybrid coupler is significantly lowered, which can lead to a large amount of size reduction for a fixed frequency operation. Besides, the third harmonic signal is suppressed to -30 dB with respect to a conventional rat-race hybrid coupler. In this case, the measured insertion loss is comparable to that of a conventional hybrid coupler.

Journal ArticleDOI
TL;DR: In this article, the authors presented a high isolation dual-frequency orthogonally polarized rectangular patch antenna utilizing microstrip feed line integrated with a defected ground structure (DGS).
Abstract: This letter presents a high isolation dual-frequency orthogonally polarized rectangular patch antenna utilizing microstrip feed line integrated with a defected ground structure (DGS) The demonstrated approach results in a significant improvement in port isolation in comparison to a conventional dual-polarized antenna fed by simple microstrip lines Measurements show an improvement of 20 dB in port isolation relative to the conventional antenna, operating at 2 and 25 GHz Image impedance of a microstrip line with DGS is controlled by the DGS geometry without modifying the dimension of the line A 150 /spl Omega/ high impedance line is effectively implemented using a microstrip line with 75 /spl Omega/ line width by incorporating the DGS

Journal ArticleDOI
TL;DR: In this article, the singlet, which contains one resonator and generates one transmission zero, is introduced as the most basic building block for modular design of elliptic filters, and a novel model, the nonresonating node model (NRNM), which contains both resonating and non-reonating nodes is then introduced.
Abstract: The singlet, which contains one resonator and generates one transmission zero, is introduced as the most basic building block for modular design of elliptic filters. Higher-order elliptic filters are designed by cascading singlets to generate the required transmission zeros. A novel model, the nonresonating node model (NRNM), which contains both resonating and nonresonating nodes is then introduced. The model allows a high level of modularity in the design of elliptic filters. Example filters are designed and measured to validate the model and the design approach.

Journal ArticleDOI
TL;DR: In this paper, the authors used compact miniaturized hairpin resonators to design cross-coupled filters with a dual-passband response of elliptic function type and treated them as a stepped impedance resonator in analysis.
Abstract: Compact miniaturized hairpin resonators are used to design cross-coupled filters with a dual-passband response of elliptic function type. The hairpin resonators are treated as a stepped impedance resonator (SIR) in analysis. In a filter, two different hairpin resonators are used to establish proper couplings required for the two design frequencies. Two filters are fabricated and measured. The results show a good agreement with the simulation.

Journal ArticleDOI
TL;DR: A backward directional coupler, composed of a conventional microstrip (C/spl mu/S) line and composite right/left-handed (CRLH) line, is proposed in this article.
Abstract: A novel backward directional coupler, composed of a conventional microstrip (C/spl mu/S) line and composite right/left-handed (CRLH) line, is proposed. This coupler is functionally backward but it is based on a forward-type coupling phenomenon. The coupler is shown to exhibit broad bandwidth and tight coupling characteristics. The theoretical circuit-model results are supported by full-wave and experimental evidence. A quasi 0-dB prototype with more than 50% bandwidth is demonstrated.

Journal ArticleDOI
TL;DR: In this article, a new LC series element based on a modified version of the split rings resonator was proposed, which is a very attractive element for compact bandpass filter design.
Abstract: A new LC series element based on a modified version of the split rings resonator introduced in is proposed. Owing to its small electrical size, the new open split ring resonator (OSRR) is a very attractive element for compact bandpass filter design. As an example, we have designed and fabricated a filter to produce a bandpass around the resonance frequency of the employed OSRRs. The filter bandwidth is controlled by the length of the transmission lines connecting the OSRRs. Sharp and deep out-of-band rejection is achieved by cascading several OSRRs. Circuit theory and electromagnetic based simulations reasonably agree with experiments.

Journal ArticleDOI
TL;DR: In this paper, a periodic microstrip leaky-wave antenna based on composite right/left-handed (CRLH) metamaterials is presented, which includes varactors modulating the capacitive loading of the unit cell and therefore the propagation constant of the structure, resulting in voltage scanning of the radiated beam.
Abstract: A novel electronically scanned periodic microstrip leaky-wave (LW) antenna based on the concept of composite right/left-handed (CRLH) metamaterials is presented. This antenna includes varactors modulating the capacitive loading of the unit cell and therefore the propagation constant of the structure, which results in voltage scanning of the radiated beam. An accurate circuit model is proposed. The antenna is demonstrated experimentally to exhibit continuous scanning in the dominant mode from backward to forward angles. The scanning range is from -10/spl deg/ at 35 V to +7.5/spl deg/ at 0 V, and broadside occurs at 9 V, at the fixed frequency of 3.23 GHz.

Journal ArticleDOI
TL;DR: In this paper, a 1-dimensional (1-D) periodic defected ground structure (DGS) for microstrip line is presented, and two improved periodic DGS circuits are designed, fabricated, and measured.
Abstract: A novel one-dimensional (1-D) periodic defected ground structure (DGS) for microstrip line is presented in this letter. Different from the periodic DGS with uniform square-patterned defects, the improved periodic DGS has a compensated microstrip line and the dimensions of the square defects are nonuniform and varied proportionally to the relative amplitudes distribution of the exponential function e/sup 1/n/ (n denotes the positive integer). A uniform periodic DGS circuit and two improved periodic DGS circuits are designed, fabricated, and measured. Measurements show that the latter exhibit more excellent performances by suppressing ripples and enlarging stopband bandwidth.

Journal ArticleDOI
TL;DR: In this article, an array factor approach of leaky-wave antennas is proposed for efficient and fast computation of the radiation patterns of complex metamaterial LW structures of arbitrary length from the analysis of a single periodic unit cell.
Abstract: An array factor approach of leaky-wave (LW) antennas is proposed for efficient and fast computation of the radiation patterns of complex metamaterial LW structures of arbitrary length from the analysis of a single periodic unit cell. This approach is demonstrated in one-dimensional and two-dimensional composite right/left-handed (CRLH) LW antennas.

Journal ArticleDOI
TL;DR: In this paper, a method to achieve the rejection of multiple spurious passbands in parallel-coupled-line microstrip bandpass filters is proposed, using a continuous perturbation of the width of the coupled-lines following a sinusoidal law, which can be modulated so that the first undesired harmonic passband of the filter is rejected, while the desired passband is maintained virtually unaltered.
Abstract: A method to achieve the rejection of multiple spurious passbands in parallel-coupled-line microstrip bandpass filters is proposed. As it was previously demonstrated by the authors, using a continuous perturbation of the width of the coupled-lines following a sinusoidal law, the wave impedance can be modulated so that the first undesired harmonic passband of the filter is rejected, while the desired passband is maintained virtually unaltered. In this letter, the scope of the method is extended to reject multiple spurious passbands by employing different periods in each coupled-line section tuned to the different bands to be rejected. Simulated and measured data show that for an order-seven bandpass filter prototype, a rejection level exceeding 30 dB is obtained in the first four spurious passbands, while the desired pass-band is kept almost unaltered.

Journal ArticleDOI
TL;DR: In this paper, the design and performance of a GaAs-based planar Schottky diodes-based multiplier chain to the 1.7-1.9 GHz band were reported.
Abstract: We report on the design and performance of a /spl times/2/spl times/3/spl times/3 frequency multiplier chain to the 1.7-1.9 THz band. GaAs-based planar Schottky diodes are utilized in each stage. A W-band power amplifier, driven by a commercially available synthesizer, was used to pump the chain with 100 mW of input power. The peak measured output power at room temperature is 3 /spl mu/W at 1740 GHz. When cooled to 120 K, the chain provides more than 1.5 /spl mu/W from 1730 to 1875 GHz and produced a peak of 15 /spl mu/W at 1746 GHz.

Journal ArticleDOI
TL;DR: In this article, a planar structure with three metal levels is proposed for band pass filters, where the central layer consists on a coplanar waveguide with periodic wire connections between the central strip and ground planes.
Abstract: A new type of compact band pass filters based on planar structures with three metal levels is proposed. The central layer consists on a coplanar waveguide (CPW) with periodic wire connections between the central strip and ground planes. In the upper and lower metal levels, split ring resonators (SRRs) are etched and aligned with the slots. The wires make the structure to behave as a microwave plasma, with a negative effective permittivity covering a wide frequency range. SRRs, which are magnetically coupled to the CPW, provide a negative magnetic permeability in a narrow frequency range above their resonant frequency. The result is a band pass structure which supports wave propagation in a frequency interval where negative permittivity and permeability coexist. The bandwidth of the structure can be controlled by tuning the resonant frequency of the upper and lower SRRs and the distance between SRRs. Fabricated prototype devices exhibit very low insertion losses in the pass band (<1.5 dB) and high frequency selectivity.

Journal ArticleDOI
TL;DR: A simple and accurate circuit model for microstrip filtering structures with slotted ground plane is presented in this article, which consists of a series inductance and shunt capacitance for the microstrip line, an ideal transmission line characterized by its impedance and electrical length for the slot, and an ideal transformer to model coupling to the slot.
Abstract: A simple and accurate circuit model for microstrip filtering structures with slotted ground plane is presented. The unit cell model consists of a series inductance and shunt capacitance for the microstrip line, an ideal transmission line characterized by its impedance and electrical length for the slot, and an ideal transformer to model coupling to the slot. The coupling mechanism to the slots resonances and subsequent emergence of transmission gaps is explained for different positions of the microstrip line. Excellent agreement with measurement is demonstrated over the broad bandwidth of dc to 20 GHz.

Journal ArticleDOI
TL;DR: In this paper, a low-power low-noise amplifier (LNA) for ultra-wideband (UWB) radio systems is presented, which uses peaking and feedback techniques to optimize its gain, bandwidth and impedance matching.
Abstract: A low-power low-noise amplifier (LNA) for ultra-wideband (UWB) radio systems is presented. The microwave monolithic integrated circuit (MMIC) has been fabricated using a commercial 0.25-/spl mu/m silicon-germanium (SiGe) bipolar CMOS (BiCMOS) technology. The amplifier uses peaking and feedback techniques to optimize its gain, bandwidth and impedance matching. It operates from 3.4 to 6.9GHz, which corresponds with the low end of the available UWB radio spectrum. The LNA has a peak gain of 10dB and a noise figure less than 5dB over the entire bandwidth. The circuit consumes only 3.5mW using a 1-V supply voltage. A figure of merit (FoM) for LNAs considering bandwidth, gain, noise, power consumption, and technology is proposed. The realized LNA circuit is compared with other recently published low-power LNA designs and shows the highest reported FoM.

Journal ArticleDOI
TL;DR: In this article, a circularly polarized shorted annular ring-slot rectenna (rectifying antenna) on a 0.5 mm thick flexible microwave laminate is proposed for the powering of portable devices operating without batteries.
Abstract: Portable devices operating without batteries are sometimes desired in wireless applications such as RFID (Radio Frequency Identification) and telemetry. A novel circularly polarized shorted annular ring-slot rectenna (rectifying antenna) on a 0.5 mm thick flexible microwave laminate is proposed for the powering of these devices. Output dc voltage of 1.3 V and axial ratio of 1.5 dB were measured when 32 dBm microwave power was transmitted at 5.8 GHz over a distance of 2 m. Comparing the results with a rectenna designed on a thick rigid laminate, similar performance was observed.

Journal ArticleDOI
TL;DR: In this paper, a parallel-coupled-line microstrip band pass filter (BPF) was proposed to improve the harmonic suppression performance of the second harmonic signal (2f/sub o/, twice the passband frequency) by enforcing consecutive patterns in coupled-line and increasing the number of grooves to the optimum values.
Abstract: In this paper, a new parallel-coupled-line microstrip band pass filter (BPF) improving the harmonic suppression performance of the second harmonic signal (2f/sub o/, twice the passband frequency) is described. It is found that the desired passband performance is improved and the harmonic passband signal is diminished by enforcing the consecutive patterns in coupled-line and increasing the number of grooves to the optimum values. The recalculation of design parameters such as space-gap between lines, line widths and lengths is not required due to the simple modification of the conventional filter by inserting periodic patterns. To evaluate the validity of this novel technique, order-3 Butterworth BPF centered at 2.5 GHz with a 10% fractional bandwidth (FBW) and order-5 Chebyshev BPF centered at 10 GHz with a 15% FBW were used. When five and three square grooves are used, over 30-dB suppression at second harmonic signal is achieved in simulation and experiment. Finally, the comparison between the characteristics of filters with square and semicircular periodic grooves has been carried out by using the simulated results.

Journal ArticleDOI
TL;DR: In this paper, a dual-mode canonical filter with dual-passband is presented for the Ka-band (30/20GHz) satellite transponder, and the measured frequency response of the filter shows good agreement with the computed one.
Abstract: Due to the complex arrangement of frequency plans and spatial coverages in modern satellite communication systems, channels that are noncontiguous in frequency may be amplified by a single power amplifier and transmitted to the ground through one beam. In this letter, a dual-mode canonical filter with dual-passband is presented. The filter adopts dual-mode technique for mass and volume reduction. Canonical structure is adopted for maximum zero realization. To validate the design technique, a six-pole dual-mode dual-passband filter of canonical structure for Ka-band (30/20GHz) satellite transponder is realized. The measured frequency response of the filter shows good agreement with the computed one.

Journal ArticleDOI
TL;DR: In this article, a power/ground planes design for eliminating the ground bounce noise (GBN) in high-speed digital circuits is proposed by using low-period photonic bandgap (PBG) structure.
Abstract: A novel power/ground planes design for eliminating the ground bounce noise (GBN) in high-speed digital circuits is proposed by using low-period photonic bandgap (PBG) structure. Keeping solid for the ground plane and designing low-period PBG pattern on the power plane, the proposed structure omni-directionally behaves highly efficient suppression of GBN (over 50 dB) within broadband frequency range from 1 GHz to 4 GHz. Although the power plane has low-period perforation, the proposed structure still performs with relatively low radiation within the stopband compared with the solid power/ground planes. The low radiation and high suppression of the GBN for the proposed structure are checked both experimentally and numerically. Good consistency is seen.

Journal ArticleDOI
TL;DR: In this article, a C-band low-noise amplifier (LNA) was designed and fabricated using GAN HEMT power devices, which can endure up to 31 dBm power from the input port.
Abstract: A C-band low-noise amplifier (LNA) is designed and fabricated using GAN HEMT power devices. The one-stage amplifier has a measured noise figure of 1.6 dB at 6 GHz, with an associated gain of 10.9 dB and IIP3 of 13 dBm. it also exhibits broadband operation from 4-8 GHz with noise figure less than 1.9 dB. The circuit can endure up to 31 dBm power from the input port. Compared to circuits based on other material and technology, the circuit shows comparable noise figure with improved dynamic range and survivability.

Journal ArticleDOI
TL;DR: In this article, a microstrip stub type compact 3-pole bandpass filter (BPF) was developed for 4.2 GHz with better than 25 dB rejection in the stopband up to 12 GHz.
Abstract: Usually a defected ground plane structure (DGS) provides only a band-reject response. However, in this work we introduce a simple band-accept circuit element in the DGS and developed a microstrip stub type compact 3-pole bandpass filter (BPF) at 4.2 GHz. The BPF has bandwidth and insertion loss 38% and 0.6 dB respectively. It has better than 25 dB rejection in the stopband up to 12 GHz.