Andrey Andrenko

Active Broad X-Band Circular Patch Antenna

This letter presents the results of experimental study of omnidirectional circular patch antenna operating in the TM010 mode. Antenna geometrical parameters have been selected on the basis of theoretical calculations. It has been shown that the antenna of this kind with VSWR les 2 and bandwidth of 18% has a conical radiation pattern with maximum oriented 36deg to the zenith. The antenna has a side radiation level of -15 dB and a cross-component level of less than -25 dB. The experimental results are in good agreement with the theoretical calculations. Employment of the one-stage HEMT amplifier makes it possible to obtain the total gain of an active antenna of no less than 10 dB. This antenna can be successfully used for mobile systems, wireless indoor communications, as well as for array applications

Scattering and mode conversion by a screen-like inhomogeneity inside a dielectric slab waveguide

In this paper, the interaction of surface guided waves with a perfectly conducting scatterer shaped as a part of a circular screen and placed into a dielectric slab waveguide is investigated in mathematically correct manner. Due to the geometry of screen the original boundary value problem is reduced to dual series equations treated further by means of the Riemann-Hilbert Problem technique. Based on this approach, the numerical solution can be obtained, theoretically, with any desired accuracy. The reflection, transmission, and radiated-field quantities are computed for both single-mode and multimode slab guides containing cavity-shaped and strip-shaped scatterers. >

Novel design of UHF RFID near-field antenna for smart shelf applications

This paper presents the design of UHF RFID read/write (R/W) antenna to be used in a variety of smart shelf retail applications. The design principle based on the EM coupling between open-ended MS feed line and periodic planar metal strips is presented. The proposed antenna can be easily customized for the required aria of smart shelf RFID interrogation. Several antenna prototypes have been designed, produced and measured. The antenna performance has been evaluated in UHF RFID system for the simultaneous detection of arbitrary oriented tagged apparel items placed on the antenna surface. The proposed antenna demonstrates excellent ability to provide strong and uniform E-field distribution at the distances up to 50 cm form the antenna surface.

Comparative study of wideband properties of planar solid and strip fractal bow-tie dipoles

Rapid development of wireless technology in recent years demands novel designs of wideband, low-profile antenna elements. Planar bow-tie dipole is a well-known antenna that can provide multiband and wideband radiation performance. This paper presents the detailed study of wideband radiation characteristics of planar solid and strip fractal bow-tie dipoles and discusses their prospective applications for multiband wireless communications antenna system. The results obtained are then compared with those for the strip bow-tie and strip triangular fractal bow-tie dipoles. ADS momentum simulator is used for full-wave EM analysis including current density and radiation pattern visualization.

Novel circularly polarized loop coupled dipole antenna

This paper presents the design principle of a novel circularly polarized printed antenna having simple unobstructed layout and single feeding port. At the same time, the proposed antenna demonstrates good circular polarization performance. The design and optimization of two antenna prototypes have been carried out for RFID applications in 953 MHz frequency band. Both simulation and measurement data on VSWR, circular polarization AR, and antenna gain are presented.

Compact frequency-tunable antenna with a GaAs switch for mobile handset

A novel compact tunable antenna for a mobile handset is proposed. The antenna occupies small 50 × 10 × 2 mm volume and covers 800 MHz, 1.7-2 GHz, and 1.5 GHz bands. The antenna is composed of a monopole element for 800 MHz and a skeleton antenna for 1.5 GHz and 1.7-2.1 GHz that cuts the inside of the planar antenna. Proposed antenna size is the same as a conventional antenna designed for 800MHz and 1.72.1GHz operation despite of the additional 1.5 GHz frequency band. The proposed antenna has achieved -6dB return loss at 800 MHz, 1.5 GHz, and 1.7-2.1 GHz bands. The total efficiency at the middle band is less than -3dB. We have clarified the mechanism of the decreased efficiency at the 1.5 GHz band and realized an efficiency improvement by utilizing a reflection-type RF switch instead of an absorption-type switch.

Low correlation antenna design for diversity handset applications

The design of compact diversity antenna for wireless handset applications has been presented. The results obtained demonstrate high potential of such a design for the handset antenna systems realizing various diversity techniques, such as switched diversity, maximal ratio combining and selection diversity. This antenna structure can also be utilized in a MIMO system, where the low mutual coupling between the antenna elements is required. It has been confirmed that the antenna radiation characteristics (radiation gain, directivity and total efficiency) satisfy the specification parameters being demanded for wireless handset applications.

Planar CP RFID R/W antennas based on EM Coupling

This paper presents the new approach to design planar circularly polarized (CP) antennas for RFID read/write (R/W) applications in UHF band. The objective of this work has been to design an RFID R/W antenna having simple unobstructed layout and single feeding port yet demonstrating good CP performance. Two RHCP antennas utilizing the principle of EM coupling from dipole element to the parasitic structure have been realized. The first design is the loop coupled dipole antenna (LCDA) where the pair of rectangular loops is placed in close vicinity of a dipole element. The second one is the dipole coupled dipole antenna (DCDA) which includes a pair of parasitic strips coupled to a dipole element. The operational principle of producing the CP radiation has been analyzed and illustrated in the detail. Both simulations and prototype measurements data demonstrating the required impedance characteristics and CP axial ratio have been obtained.

Modeling and design of 2-element dual-band ceramic chip handset antennas

This paper presents the modeling and design of 2-element compact ceramic chip antenna for UMTS/GPS dual-band mobile handset applications. First, the design of ceramic chip monopole integrated with a simple matching circuit will be explained. The radiation characteristics including high gain and total efficiency of the proposed compact antenna element will be presented. Next, 2-element antenna system for dual-band handset design where one antenna element is used for UMTS operation while the another one works as an assisted GPS (A-GPS) antenna will be introduced. Parametric study illustrating the effect of antenna elements separation on the mutual coupling between antenna ports will be analyzed. It has been shown that low mutual coupling is the result of strong current being induced on the 3D monopole placed inside high density dielectric ceramic pad. Mobile handset applications of the proposed compact 2-element antenna system will be discussed in the details at the Conference.

Planar dual-band spiral monopole antenna

The design of planar spiral monopole antenna and the details of antenna dual-band operation are presented in this paper. One-turn spiral geometry has been implemented in order to produce two different modes of printed monopole antenna. Optimizing the antenna layout makes it possible to control the frequency bands and thus to design antennas used for different applications, such as 3G/4G mobile terminals and human BAN wireless nodes. Important information on the final-paper submission procedure is also provided.