소형 안테나 ( Small Antennas )

Background and History. Resonator and Filter Topologies. Baw Device Basics. Design and Fabrication of BAW Devices. FBAR Resonators and Filters. Comparison with SAW Devices. Films Deposition for BAW Devices. Characterization of BAW Devices. Monolithic Integration. System-in-Package (SiP) Integration. Index.

RF bulk acoustic wave filters for communications

We report the first experimental generation of high-order Mathieu beams and confirm their propagation invariance over a limited range. In our experiment we use a computer-generated phase hologram. The peculiar behaviour of the vortices in Mathieu beams gives rise to questions about their orbital-angular-momentum content, which we calculate by performing a decomposition in terms of Bessel beams.

Holographic generation and orbital angular momentum of high-order Mathieu beams : Special issue on atoms and angular momentum of light

Recently, orbital angular momentum (OAM) based vorticose communication has attracted much attention because of its potential to significantly increase the spectrum efficiency (SE) of wireless communications. However, the multiple radio frequency (RF) chains used for multiple OAM modes lead to an unexpected cost for wireless vorticose communications. In this paper, we first propose the mode modulation (MM) based OAM system to allow multiple OAM modes sharing a common RF chain. The proposed MM cannot only reduce the hardware cost, but also boost the SE by introducing the mode as an additional dimension for data transmission. Moreover, without the channel state information (CSI) feedback, we develop an equal-probability mode modulation (EMM) scheme to maximize the SE of MM-based OAM systems with the limited RF chains. In addition, with the CSI feedback, we develop a Huffman coding based adaptive mode modulation (AMM) scheme, which can adaptively choose the OAM modes to further increase the SEs of OAM-based wireless communications. We also develop the joint power and probability allocation policy for the AMM scheme to achieve the maximum SEs for OAM-based vorticose communications. Numerical results demonstrate that the MM can offer a new mode dimension for vorticose communications and the AMM scheme can achieve larger SE than the EMM scheme.

Mode Modulation for Wireless Communications With a Twist

Electromagnetic (EM) waves with helical wavefront carry orbital angular momentum (OAM), which is associated with the azimuthal phase of the complex electric field. OAM is a new degree of freedom in EM waves and is promising for channel multiplexing in communication system. Although the OAM-carrying EM wave attracts more and more attention, the method of OAM generation at microwave frequencies still faces challenges, such as efficiency and simulation time. In this work, by using the circuit theory and equivalence principle, we build two simplified models, one for a single scatter and one for the whole metasurface to predict their EM responses. Both of the models significantly simplify the design procedure and reduce the simulation time. In this paper, we propose an ultrathin complementary metasurface that converts a left-handed (right-handed) circularly polarized plane wave without OAM to a right-handed (left-handed) circularly polarized wave with OAM of arbitrary orders and a high transmission efficiency can be achieved.

Ultrathin Complementary Metasurface for Orbital Angular Momentum Generation at Microwave Frequencies

In this paper, a compact multiband CPW-fed monopole antenna is proposed. The designed antenna has a simple structure, which consists of a rectangular radiating patch with two symmetrically structured meandered line slots on both sides and a CPW-fed 50 Ω microstrip line. The designed antenna occupies only 23 × 23 mm2 size on a FR-4 substrate sheet which makes it a good candidate for wireless mobile communications. Triple-band functionality is realized by making slots on patch to form a meandered strip on both sides of the rectangular radiating patch. These triple bands are suitable for Bluetooth, WiMAX, and WLAN applications, which are operating at 2.4 GHz, 3.5 GHz, and 5.5 GHz, respectively. The fabricated and characterized antenna prototype is having a good omnidirectional and directional radiation pattern in both H-plane and E-plane for the specified bands, respectively.

Compact Triple-Band CPW-Fed Monopole Antenna for Bluetooth/WiMAX/WLAN Applications

A rectangular patch antenna with π shaped slot is proposed as a miniaturized antenna element with a gain of 5.83 dB for WLAN (5.2 GHz) application. This compact π shaped slot antenna is used as a r...

A Pi-Shaped Slot Antenna for 5.2 GHz WLANMIMO Application

Discriminatory Features Based on Wavelet Energy for Effective Analysis of Electroencephalogram During Mental Tasks

A single band notched Coplanar Waveguide Antenna using complementary split ring resonators is proposed and investigated which is working on WLAN and C-Band applications. The proposed antenna can reject single frequency band by etching Circular Split Ring Resonators (CSRRs) on the radiating patch. The single stop band of the proposed CPW antenna are 4.6GHz–5.3GHz with a reference level of Sn = −10 dB. The center frequency of the first notched band is 5.0GHz at which the wireless WLAN (Upper WiFi) service is assigned. The proposed antenna operates from 2482 MHz to 2984 MHz for voltage standing wave ratio (VSWR) less than 2, except one frequency notched band of 4.6GHz–5.3GHz

A single band notched CPW antenna design

In this paper, the microstrip antenna consist of a planar resonant radiating element parallel to, but separated, from a ground plane by a thin dielectric substrate (t <<λ) was designed and simulated on EM software. This antenna is fabricated on RT Duroid substrate of dielectric 2.2, thickness 0.8 mm. This antenna was feed by microstrip transformer. Linearly polarized circular shape antenna was designed at centre frequency 10 GHz. The E & H — plane radiation patterns were shown

Madhur Deo Upadhayay

Papers

Compact Triple-Band CPW-Fed Monopole Antenna for Bluetooth/WiMAX/WLAN Applications

A Pi-Shaped Slot Antenna for 5.2 GHz WLANMIMO Application

Discriminatory Features Based on Wavelet Energy for Effective Analysis of Electroencephalogram During Mental Tasks

A single band notched CPW antenna design

Study on circular planar antenna