We present the design, realization and performance of a millimeter-wave patch antenna with frequency reconfiguration capabilities generated by integrating ferroelectric interdigitated tunable capacitors (FIDC). The tunable capacitors are based on Ba0.8Sr0.2TiO3 (BST) ferroelectric layers and exhibit very good and stable performances over the microwave and millimeter-wave bands, with a maximum tunability of 40% for a bias voltage of 100 V. The ferroelectric layers have been integrated in the slot-loop excitation circuit of the antenna and their Direct Current (DC) polarization allows a continuous frequency reconfiguration of the antenna around 30 GHz. An electrical model of the whole radiating device has been developed allowing extracting the range of capacitance values to be integrated into the excitation slot for an optimum frequency tuning. The fabricated antenna shows a variation of the operation frequency from 28.5 GHz to 34.95 GHz, corresponding to a frequency tuning of 22.6%. The antenna is very well matched all over the operating frequency band, with total efficiencies between 20% (0 V bias on FIDCs) and 65%(100 V bias).

This article presents the development of an antenna device operating with a right-hand circular polarization (RHCP) for Global Navigation Satellite Systems (GNSSs) applications, operating in the frequency bands L1 (1.5756 GHz), L2 (1.227 GHz), and E6 (1.278 GHz). The antenna exploits the potential of biased ferrite materials to naturally generate a circular polarization. In addition, to achieve a right-hand circular polarization over a wide frequency band, the antenna uses a carefully selected and polarized ferrite material to ensure that the device operates where the effective permeability of the ferrite has a negative real part. It also allows the reduction of antenna dimensions due to the high permittivity of ferrites. All performances in terms of impedance matching and radiation pattern are reported, and the concept is validated by the prototype measurements.

This work presents a proof of concept for a highgain, continuously beam-scanning Ka-band antenna, designed for collision avoidance radar. The antenna features a modified dielectric lens to mitigate scanning loss, fabricated using lowcost Polylactic Acid (PLA) through additive manufacturing. A slotted substrate integrated waveguide (SIW) serves as the feed system, meeting compactness requirements. The resulting antenna system combines a cost-effective modified lens with a 6slot SIW frequency-scanning array and a single transmission channel, enabling frequency scanning over an 80 degrees angular range with a simulated realized gain of around 14 dBi. The final prototype is currently under fabrication process for experimental validation.

This article describes the development, the design and the measurement of a circularly polarized ultra-miniature antenna. The modeled device takes advantage of the magnetic properties of ferrite materials to achieve the desired specifications. Indeed, the antenna is operating at a frequency where the effective permeability is greater than one and the permeability has a negative real part, i.e., in the zone between the $\mu $ and $\mu _{eff}$ resonances of the ferrite. The dimensions of the designed antenna are about $\mathrm {} (\mathrm {\lambda }_{0}/23.6)\times \mathrm { } (\mathrm {\lambda }_{0}/20.7)\times \mathrm { } (\mathrm {\lambda }_{0}/29.4)$ at 2.42 GHz and a good circular polarization is achieved at the central operating frequency of the device, with a boresight axial ratio (AR) of 1.6 dB. This article is based on the modal study of a ferrite cavity which will be presented and detailed in a first step. The physical properties of the antenna and related material (dimensions, ferrite internal magnetic field, the saturation magnetization, etc.) will be deduced from this modal study and from the resolution of the wave equation inside a cylindrical ferrite cavity. All the antenna performances in terms of impedance matching, axial-ratio, and radiation pattern are reported and commented. This concept is finally validated by the measurement of a prototype.

The reaction-diffusion principle imagined by Alan Turing in an attempt to explain the structuring of living organisms is leveraged in this work for the procedural synthesis of radiating metasurfaces. The adaptation of this morphogenesis technique ensures the growth of anisotropic cellular patterns automatically arranged to satisfy local electromagnetic constraints, facilitating the radiation of waves controlled in frequency, space, and polarization. Experimental validations of this method are presented, designing morphogenetic metasurfaces radiating far-field circularly polarized beams and generating a polarization-multiplexed hologram in the radiative near-field zone. The exploitation of morphogenesis-inspired models proves particularly well suited for solving generative design problems, converting global physical constraints into local interactions of simulated chemical reactants ensuring the emergence of self-organizing meta-atoms.

This paper presents the use of pixel-type radiating elements in the context of broadband beam steering. The elements are composed of a resonant cavity topped by a frequency selective surface, fed via a patch antenna and filled with dielectric substrates. This pixel antenna has a wide -10 dB matching band from 1.22 to 1.61 GHz, which corresponds to a 27% fractional bandwidth. It has an angular aperture greater than 124° and a realized gain between 3.3 and 3.8 dBi over the whole matching band. An array composed of 5 elements has been simulated and allows a steering on a range of ±60° in the E plane while keeping the gain variation below 3 dB. A prototype has been manufactured and presents a steering capacity between -56 and 53° on the whole band with side-lobes levels lower than -8.1 dB whatever the angle.

A single fed, compact and circularly polarized patch antenna operating in three frequency bands is proposed in the present paper. This patch antenna uses a polarized ferrite substrate which therefore has the property of naturally generating circularly polarized waves. The modelling process of a compact antenna having dimensions of $\frac{\lambda_{0}}{10}\times\frac{\lambda_{0}}{9.5}\times\frac{\lambda_{0}}{27}$ at 3GHz and presenting three circularly polarized modes is exhibited. A prototype measurement has been carried out for an experimental validation of the simulated results.

The purpose of this article is to show the strong potential of ferrite materials to improve antennas performances. Indeed, the combination of circular polarization with miniaturization and multiband frequency operation makes ferrites the ideal solution to optimize antenna's characteristics. In this work, the complete development of a miniature antenna having dimensions of (λ 0 /9.6)×(λ 0 /9.1)×(λ 0 /27.4) at 3.13 GHz, operating over three frequency bands, and having a circular polarization is detailed. The benefit of incorporating such ferrite materials within an antenna on the radiation efficiency, the impedance bandwidth, and the axial ratio is presented. The prototype measurement will validate this development and the simulation results.

The design and measurement of a 17.3 – 21.2 GHz corrugated horn as a feed for a compact antenna test range (CATR) is presented

A single fed, compact and circularly polarized patch antenna operating in three frequency bands is proposed in the present paper. This patch antenna uses a polarized ferrite substrate which therefore has the property of naturally generating circularly polarized waves. A prototype measurement has been carried out for an experimental validation of the simulated results.

This paper explores a new concept for the design of high scanning-range phased array antennas: the Interleaved Parasitic Arrays Antenna or IPAA. In this concept, we use periodic parasitic elements and the generator impedance to control the Active Voltage Standing Wave Ratio (AVSWR) over a wide scanning range. This new array architecture comes with a design methodology enabling a smooth step-by-step design process aiming at reducing the need for full-wave calculations. First, a numerical dual-polarization design is presented in detail to illustrate the methodology and to give the design keys to the reader. Then, a prototype working in the 5G C-band between 3.4 and 3.8 GHz (11% bandwidth) was designed using this methodology and measured for a 36-element array. It is meant to demonstrate and validate the mutual coupling management done by the interleaved parasitic arrays and the design process accuracy. Good correspondence between measurements and simulation was found and the proposed unit cell with its corresponding tile can be integrated in a larger phased array with active modules to perform beam steering over an important scanning range without deteriorating the AVSWR. The proposed unit cell is designed for a high-scanning range going from $\theta =0^{\circ }$ to $\theta = 70^{\circ }$ for every $\varphi $ -directions and shows an active reflection coefficient for an infinite array below −13.6dB.

Parasitic element antennas are among the simplest antennas for basic beamforming, based on the works from Harrington’s in the 70’s. However, they suffer from limitations with only one driven element. This work presents an improvement of this principle with an array of parasitic elements with multiple excitations and an optimization of the matching while the beam is steered. A prototype in S-band has been measured to validate the ability of this parasitic antenna array and to demonstrate its tradeoff between performances and the simplicity of the design.

This letter describes a compact isoflux X-band payload telemetry and data handling antenna with simultaneous dual circular polarization for low earth orbits satellite applications. The main objective of this antenna is to use polarization diversity to improve the efficiency of the payload telemetry link. Some solutions have already been proposed to that end, but the studied antenna combines both good electromagnetic performances and compactness. This high-power capability waveguide antenna presents an axial ratio lower than 2.5 dB over the 8.025–8.4 GHz frequency band at the limit of coverage, i.e., 65°, for any azimuth angle (ϕ). It has been designed, realized, and successfully measured.

We present the integration of GeTe (Germanium Telluride), a phase change material (PCM), within the structure of an antenna operating in the millimeter wave domain (~ 30 GHz) in order to make it reconfigurable in three polarizations: a linear polarization (LP), a left hand circular polarization (LHCP) and a right hand circular polarization (RHCP). The device is based on a conventional patch antenna excited by a microstrip line with the GeTe material integrated into the four corners of the patch. The phase change between the insulating (OFF) and metallic (ON) states of this material is controlled by direct irradiation using ultraviolet (UV) short laser pulses and allows the reconfigurability of the antenna between an LP, an LHCP and an RHCP. The measured performances of the fabricated device show axial ratios of less than 3 dB over a 400 MHz of bandwidth around 29.5 GHz with total efficiencies up to 75 % for the circularly polarized configurations and a maximum gain up to 8.3 dBi for the linear polarization states.

We present the integration of Germanium Telluride (GeTe), a phase change material (PCM), within a conventional patch antenna operating in the millimeter wave domain (~ 30 GHz). The GeTe is integrated within the four corners of a metallic patch antenna, which is excited by a microstrip line. The phase changes between the insulating (OFF) and metallic (ON) states of GeTe will be controlled using shorts ultraviolet (UV) laser pulses. That allows the reconfigurability of the device between a linear polarization (LP), a left hand circular polarization (LHCP) and a right hand circular polarization (RHCP). Simulated results of antenna show total efficiencies up to 75 % for the circular polarization (CP) and a 3 dB bandwidth of axial ratio (AR) over 350 MHz around 29.5 GHz.

Spatial telemetry links on nanosatellites require more and more reconfigurable beam antennas to improve the Earth coverage. The bi-mode Agile Radiating Matrix Antenna (8.0-8.4 GHz) was successfully designed to solve such kind of problems by using an isoflux mode associated with a switchable directive one. However, such an antenna introduces some manufacturing problems for the isoflux mode, mainly due to the small available volume on the nanosatellite platform. This paper describes a solution to this problem thanks to the ARMA concept. A comparison between theoretical and experimental results for the isoflux mode in circular polarization is presented to validate the results.

This review deals with the design of a new reconfigurable beam antenna used to improve the efficiency of spatial telemetry links on Nano-Satellite. Advances in this domain show the needs to serve some applications with special electromagnetic beams and polarization patterns especially from LEO and MEO Space-Earth links. The RF front end must be capable to switch from high gain directive pattern to special pattern called Isoflux where the gain must be concentrated at high elevation angles with another challenge also the circular polarization. The content is a part of the CNES project that serves for multimode beam forming applications. This agile beam antenna is not built on the well-known array concept: AESA stands for Agile Electronically Scanned Array but using a new approach called ARMA standing for Agile Radiating Matrix Antenna. Contributions will show the small size elementary antenna of ARMA called Pixel, the polarization circuits that fit the challenges of the Nano-Satellite dimensions, the enhancement in the circular polarization requirements and theoretical and experimental comparison. Special beam forming required in the telemetry applications are achieved with better gain especially for the aim of wide beams. The use of the new approach will show the beam forming advantage of radiating the energy to high elevation angles.