A Miniaturization Technique of a Compact Omnidirectional Antenna

This paper discusses a miniaturization technique of a compact omnidirectional antenna. A slot loading technique is applied to a well-known low-profile antenna structure whose radiation characteristics are similar to equivalent monopole ones. An equivalent circuit which models the antenna input impedance including the slot effect is also developed in order to illustrate the antenna working principle. The typical dimensions (width x height) of the obtained antenna are λ0/11 x λ0/75 (λ0 is the free space operating wavelength) which makes it a miniature antenna that can be integrated inside small wireless sensor nodes using narrow band communication systems. Its performances are in accordance with classical fundamental limits, the operating bandwidth and efficiency are significantly reduced with the antenna size reduction

Characterization of Antennas on Dielectric and Magnetic Substrates Effective Medium Approximation

This paper presents a study of the effective medium approximation of a monopole antenna printed on either a dielectric or a magnetic substrate. Simple analytical formulas to determine the effective permeability of such an antenna have been proposed and validated. For this type of antenna as μr increases, the effective permeability will reach the value of 2 (maximum) whereas, with the dielectric substrate, the effective permittivity continues to rise when increasing εr. This shows that, for very high permeability values, we will always have a size reduction below 30%

A Frequency Agility Technique on a Miniature Omnidirectional Antenna

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Compact Multiantenna

Planar inverted-f antenna (PIFA) and notch antenna are combined within a compact 2-port MIMO antenna. Electrical and magnetic duality of the two antennas avoids a critical coupling and best performances can be expected for multiple-input multiple-output (MIMO) communication. When excitation of notch antenna is optimized properly, the notch length can be short enough so that the two antennas can be colocated in a single compact volume. This compact multiantenna design is suitable for integration in MIMO handheld terminals. A prototype for broadband network application in 3.4–3.8’GHz frequency band has been characterized in anechoic chamber

Characterization of the coverage uniformity of an antenna based on its far-field

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A Compact Dual-Band Notch Antenna for Wireless Multistandard Terminals

International audienceA compact planar dual-band notch antenna for wireless multistandard handset terminals is designed and experimentally demonstrated. The design technique is detailed first in the ideal case of a notch antenna loaded with a lumped capacitance and fed through an ideal matching network. Next, the implementation on an FR4 substrate with a finite ground plane compatible with a handset is presented. The simulated and experimental performances demonstrate a dual-band response (815-1010 and 1680-3600 MHz) corresponding to the main cellular and short-range standards (GSM-900, DCS-1800, IMT-2000, LTE, WiFi-802.11b/g/n , and WiMAX) with a total efficiency greater than 60%

Miniature reconfigurable multi-antenna system for IMT-Advanced band

International audienceThis paper presents a compact reconfigurable multiantenna system addressing the IMT-Advanced band. The antenna system is built using compact antennas whose miniaturization is obtained by limiting instantaneous operating bandwidth. Frequency agility technique it then used to enlarge the operating frequency in accordance with the whole operating band and communication standard waveform. Good decoupling performances are achieved with the multi-antenna device thanks to a particular arrangement of the antennas. This system has been introduced for small mobile terminals, where form factor is very important. The use of two antennas could bring benefits to limit fast fading effects introduced by mobilit

Caractérisation d'antenne miniature par réflectométrie en champ lointain

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