Jean-Marc Ribero

Comments on "A new model for calculating the input impedance of coax-fed circular microstrip antennas with and without air gaps" [with reply]

For original paper by Abboud et al. see IEEE Trans. Antennas Propagat., vol.38, p.1882-5 (1990). In the original paper, the resonance frequency of coax-fed circular microstrip antennas with and without air gaps has been modeled (in its Section III) by incorporating and rearranging some results previously reported by others. The present author, while working with the formulas of that Section III noticed a discrepancy in (8) and (9). This has been investigated thoroughly and the observations are presented. A brief reply is given by Damiano et al.

A New Magneto-Dielectric Material Loaded, Tunable UHF Antenna for Handheld Devices

In this letter, the impact of a magneto-dielectric resonator on a DVB-H antenna is investigated. A frequency reconfigurable antenna using a folded monopole antenna structure and varactor diodes is proposed. Two different designs are realized with and without the resonator. A measured instantaneous -6-dB bandwidth wider than 8 MHz is obtained continuously between 470 and 862 MHz for both prototypes. Design methodology is described. Measured return loss, gain, directivity, and radiation pattern are presented for different frequencies.

Reconfigurable Antenna for Future Spectrum Reallocations in 5G Communications

This letter presents a reconfigurable antenna for mobile terminals with extended band coverage obtained by using a digitally tunable capacitor (DTC). The antenna structure is matched permanently over high frequency bands including DCS/PCS, UMTS, LTE 1800/2600, and 3.5-GHz bands. Concerning the sub-GHz bands, several reconfigurable states enable a full coverage of LTE 600/700 and GSM 850/900 standards, as well as expected spectrum reallocations for 5G communications. With dimensions of 40 ×10 ×6 mm3 for the antenna and 130 ×70 ×0.8 mm3 for the whole printed circuit board (PCB), this structure is compatible with any mobile terminal.

Light and Low-Profile GSM Omnidirectional Antenna

In this letter, an antenna operating over the GSM band is proposed. Thanks to the use of a foam material as dielectric substrate, the prototype of this antenna is particularly light. It has a very low profile with overall dimensions equal to 0.31λ × 0.31λ × 0.09λ at the GSM center frequency, and it exhibits an omnidirectional radiation pattern similar to that of a classical half-wave dipole.

Mobile phone antenna for 2G, 3G and 4G standards

In this letter, a novel mobile phone antenna for 2G, 3G and 4G standards is presented. Based on the folded inverted-L antenna associated with a ground stub, the proposed structure can operate in all the different bands of mobile telecommunications (GSM/UMTS/LTE). With a volume of 68×17 mm2 and placed on a FR4 Epoxy substrate, total efficiency of this structure is higher than 55% in the lower band (700-960 MHz) and 77% in the higher one (1615-2700 MHz).

Reconfigurable miniature antenna for DVB-H standard

In this paper a new active antenna for DVB-H standard is presented. PIN diodes are used to switch the antenna to the desired frequency band, and a varactor diode adjusts accurately the working frequency. By combining the switching of 3 PIN diodes and the control of the varactor diode capacitance, this miniature PIFAs type antenna is covering the whole UHF DVB-H standard frequency band (470–862 MHz).

Planar low profile and gain enhancement of printed antennas using EBG structures

This study is the extension of a work which we have already started on the miniaturization of a printed antenna by using electromagnetic band gap structure (EBG) of mushroom-like type [1]. In addition to the miniaturization, our objective in this study aims to extend the bandwidth and enhanced the gain of this antenna by design of a second EBG structure with the same mushroom-like type. Thus, we demonstrate that the EBG structures are the good candidates for the design of antennas characterised by low profile, wide band and high gain.

Stratospheric platform for telecommunication missions

This paper presents the design of a stratospheric platform “Stratobus” which would among other things, perform civil and military telecommunications missions. This type of system has the potential to effectively complement existing satellite and terrestrial networks, for a much lower cost and deployment effort.

Synthesis of miniature pattern-reconfigurable antennas for smart wireless sensor nodes

This paper presents an approach for the synthesis of pattern-reconfigurable antenna suitable for integration into smart wireless sensor nodes. As a proof-of-concept, a simple antenna configuration capable of steering the radiation main beam towards two opposite directions is discussed. The antenna exhibits a good impedance match in the WiFi band, compact dimensions (0.47λ × 0.2λ × 0.1λ), and high gain (7.56 dBi) and front-to-back ratio (11.26 dB).

New reconfigurable small antenna for DVB-H and GPS standard

This paper presents a new miniature reconfigurable DVB-H and GPS antenna for a portable TV or tablet PC device. The antenna consists in a Printed-Inverted-F-Antenna (PIFA) loaded by a varactor diode. The radiating element has a size of 30*30*5 mm3 and is mounted on a 230*130mm2 ground plane. This antenna is able to maintain a return loss below -10 dB on a 8 MHz bandwidth reconfigurable channel from 450 to 900 MHz and cover a 50 MHz bandwidth around 1.575GHz for the GPS standard. Then, this radiating element reaches to cover the whole frequency band specification of the DVB-H standard while keeping a good efficiency despite of the strong miniaturization