The Infona portal uses cookies, i.e. strings of text saved by a browser on the user's device. The portal can access those files and use them to remember the user's data, such as their chosen settings (screen view, interface language, etc.), or their login data. By using the Infona portal the user accepts automatic saving and using this information for portal operation purposes. More information on the subject can be found in the Privacy Policy and Terms of Service. By closing this window the user confirms that they have read the information on cookie usage, and they accept the privacy policy and the way cookies are used by the portal. You can change the cookie settings in your browser.
A compact wideband quarter-wave transformer using microstrip lines is presented. The design relies on replacing a uniform microstrip line with a multi-stage equivalent circuit. The equivalent circuit is a cascade of either T or π networks. Design equations for both types of equivalent circuits have been derived. A quarter-wave transformer operating at 1 GHz is implemented. Simulation results indicate...
The proposed paper presents two I-shaped substrate slotted flexible microstrip patch antennas with reduced ground for radiolocation and military applications. The proposed antennas employ cellulose acetate having dielectric constant (∊r) of 4.2 as the substrate. The copper having conductivity of 5.95 × 108 Siemens m−1 has been used for designing of patch and ground. The substrate, patch slot and ground...
This paper work is about a transimpedance amplifier which have very high gain and sensitivity designed using cadence CMOS 0.18 μm technology with supply voltage of 1.8 V dissipates power 43μW suitable for current sensing signals from a sensor, molecular and nanodevice system. The integrator based circuit followed by an ADC. Because of the ability to handle large standing currents, the circuit is competent...
A compact circular patch with slotted meander line (CPSM) microstrip monopole antenna is proposed for X-band applications. Symmetrical circular patches with rectangular slots on either side of monopole feed line to enhance the bandwidth and gain. Impedance bandwidth of proposed antenna is 11.5 %. The operational frequency range of CPSM antenna is 10.48 GHz to 11.74 GHz (1.26GHz bandwidth). The size...
In this paper, bow-tie antenna with defected ground structure (DGS) has presented. The radiating element is bow-tie antenna, two concentric ring slots are presented on it for producing the circular polarization (CP). Rectangular patch is loaded to bow-tie antenna for enhance the gain. On the ground plane four equal bow-tie slots are considered for enhancing the impedance bandwidth upto 10.3%. It is...
In this study, A multi band and dual band antenna using slot stepped-impedance resonators(SIR) and coplanar waveguide (CPW) feeding have been investigated. All of the proposed antennas are fabricated on 1-mm FR4 substrates with a dielectric constant of 4.4 and a loss tangent of 0.02. In comparison to the conventional uniform — impedance resonator (UIR), the SIR shows a better control over spurious...
The application of nullors in bandwidth design of amplifiers are discussed. Given an analog circuit and a desirable frequency response, the proposed methodology tries to modify the circuit to follow the response from a model circuit that performs the desirable frequency response. This is done by adding one or more feedback sub-circuits to the analog circuit so that its response can follow the response...
This paper demonstrates a power amplifier (PA) design procedure for achieving high peak efficiency over a wide bandwidth. A harmonic load-pull is performed over the desired frequency range resulting in theoretically optimum load impedances. Analysis of wide bandwidths where the harmonic bands overlap with the fundamental band and lower harmonic bands are performed. Practical impedances are found through...
A wideband Gallium Nitride (GaN) HEMT power amplifier (PA) achieving 7.6W output power over 1.1 GHz bandwidth at fo = 2.75 GHz is presented. A systematic design and synthesis of wideband low-pass matching networks realizing optimal fundamental impedance is applied. These techniques have produced amplifiers with increased output power, efficiency and very large fractional bandwidth. Additionally, the...
This article, the FM bandwidth scaling technique under injection locked and super-harmonic injection locked phenomenon, which explained by forcing oscillation perspective with multi-time variable technique is presented. By forcing FM signal to harmonic oscillator, the FM bandwidth can be scaled. This scaling technique separated in two situations, the first one is an expansion technique under injection...
In this paper, we present a new design of a compact power divider based on the modification of the conventional Wilkinson power divider. In this new configuration, length reduction of the high-impedance arms is achieved through capacitive loading using open stubs. Radial configuration was adopted for bandwidth enhancement. Additionally, by insertion of the complex isolation network between the high-impedance...
A conventional symmetric Zig-zag antenna is improved by adding a shunt shaped dipole at the feeding terminals or a shaped dipole as parasitic reflector, this dipole results in an increment of radiated gain in forward direction while remaining the wider frequency bandwidth of Zig-zag antenna. By means of the method of moments with piecewise-sine bases and Galerkin's procedure, the Zig-zag structure...
A new type of broadband miniature antenna consists of helical dipole folded by central conductor is presented in this paper. Besides a brief analysis, the experimental results show the good performances of wider bandwidth (25%–40%), higher input impedance(about 200 Ohms), and flexible for designing, it is suitable to be used as both mobile vertical antenna and excitor of Yagi antenna.
This paper introduces detailed information about a miniaturized compact super broadband printed antenna. The antenna consists of a semicircular patch, microstrip line and a partial ground plane, which is fabricated on a low cost, commercially available FR4 substrate. The overall size of the dielectric substrate is 38 × 43 × 1.5 cubic millimeter. This simple structure of the antenna has an impedance...
We present a fully integrated auto-transformer-based power amplifier with totem-pole driver exhibiting a very high bandwidth. In order to simplify the design process a structural analysis and optimization method for the transformer are presented as well as an analytical method to ensure the optimum load line at the transistor. The circuit was implemented in a 0.25 μm SiGe BiCMOS technology and was...
In this paper, two techniques are proposed using bulk-driven approach, which improves the performance of OTA. The proposed OTAs are designed and simulated on Tanner EDA Tool using 0.18 μm standard CMOS process technology. The effectiveness of using the current-shunt auxiliary amplifier, folded-cascode amplifier and replica chain self-biased technique in bulk-driven OTA results in improved DC gain...
The design of a small printed-log-periodic antenna, loaded with an active matching network, for multiband applications is presented. A well-known, low-cost and low-profile antenna is re-engineered for including an additional impedance bandwidth in the lower UHF-band. The design method includes the use of the recently introduced sensitivity parameter Sens in order to find a suitable location for a...
The paper presents a fast design methodology to achieve a circular polarizer with a relatively low thickness of one-fifth of a free-space wavelength. A three-layer planar structure is devised to exhibit transparency to both TE and TM polarized fields while imparting a quadrature phase difference between them, as required for the generation of circularly-polarized fields. The structure is designed...
Practical Antenna Design for handheld devices is demonstrated through the utilization of the modal/Eigenmode theory of antennas. Here, a review of the underlying design fundamentals is outlined. Next, a design example featuring the antenna design of a modern smartphone is presented. The design cycle is simplified through finding an antenna with appropriate complex resonance frequency to cover a required...
In this paper, we present an approach to design conformai HF band multi-antenna system for aircraft using the theory of characteristic modes. The whole antenna system generates omni-directional radiation pattern at 18 MHz, NVIS radiation pattern at 8 MHz and downward radiation pattern at 28 MHz. The antenna system is realized by mounting a set of exciters on the aircraft to excite the currents on...
Set the date range to filter the displayed results. You can set a starting date, ending date or both. You can enter the dates manually or choose them from the calendar.