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Two dual reflectarray antennas able to provide an European coverage and beam scanning over 8° respectively have been presented. An accurate technique has been proposed for the analysis of dual-reflectarray antennas, which takes into account the angle of incidence of the field impinging on main reflectarray cells. Two 50-cm antenna demonstrators with the same geometry have been manufactured and measured...
A 1.1-m reflectarray antenna has been designed, manufactured and tested to fulfil the requirements of a satellite antenna in Ku-band that provides South American coverage in Tx and Rx. The reflectarray cells consist of four dipoles for each polarization in two dielectric layers, which were selected because of their simplicity and high performance. The dipole dimensions are optimized in all the reflectarray...
A new paradigm for the design of reflectarrays is introduced. The proposed methodology allows the designer to specify constraints/simplifications on the antenna surface current distribution thanks to an innovative exploitation the non-radiating (NR) component, which is regarded a powerful additional degree-of-freedom (DoF) in the synthesis process. An illustrative example is presented, aimed at nulling...
Two techniques are compared for the crosspolar optimization of reflectarray antennas using a full-wave analysis technique based on local periodicity directly in the optimization process within acceptable computing time. The first one is based on the Levenberg-Marquardt Algorithm (LMA) while the second technique is based on the generalized Intersection Approach framework using the LMA as backward projector...
One of the most relevant challenges of next generation in-body devices consists in enhancing the medical applications of wireless networks qualitatively. The current standard does not allow high data rate wireless connections between implanted nodes. UWB systems have been considered as a potential candidate for future in-body devices. To establish a proper link within UWB, antenna matching should...
In this paper the performance of TM21 resonance-mode circular patch antennas embroidered with different stitching patterns is discussed and compared. The goal is to investigate the difference in the performance when the antenna is embroidered with stitches following the antenna current paths as opposed to some simple patterns such as horizontal and vertical ones. This creates an alternative solution...
The wireless link between an implant and an off-body gateway may be difficult to secure due to the fact that electromagnetic waves quickly attenuate as they propagate through human tissues. Depending on the depth of the implant within the body, the signal strength may be quite weak by the time the waves reach the skin. In order to address this problem, a digitally assisted repeater antenna has been...
In this paper a novel design of an UE (User Equipment) antenna for the 60-GHz band is presented. The antenna was realized on LTCC A6M-E substrate to ease a later integration with the RF-chipset on a single module. To satisfy the requirement of a relative bandwidth of 15 % an electrically thick substrate was utilized, which unfortunately leads to an undesired excitation of surface waves. A suppression...
This paper presents a new topology for a wire-grid antenna array which operates at 60 GHz. The array consists of ten λg/2 dipole radiators connected via non-radiating connectors. Both radiators and connectors are placed on top of narrow silicon walls. The antenna is fed with a coplanar microstrip lines placed at the other side of the wafer and is connected with its feeding transmission lines using...
A simple and wideband subarray for D-band applications is presented in this paper. The proposed multilayer subarray consists of 2 × 2 cavity-backed slot subarray fed by a ridge gap waveguide transmission line. The simulated results show that the proposed subarray has a relative impedance bandwidth of 22.5% with input reflection coefficient better than −10 dB over the 126–158 GHz frequency band. An...
UWB systems have been proposed as a candidate for the next generation of in-body applications. In order to perform reliable UWB channel measurements, implantable antennas should work in the propagation medium properly. To assess the UWB channel performance, in-body antenna matching should be assured. Besides, an omnidirectional radiation pattern in order to communicate with a sensor array located...
In this paper, we investigate the characteristics of the composite fading observed in non-line-of-sight (NLOS) off-body communications channels using the η-μ/inverse gamma distribution. We use a number of different datasets obtained from NLOS off-body measurements which have been performed in a range of different environments at 5.8 GHz and 60 GHz. In all cases, the bodyworn node was positioned on...
The paper considers a backhaul network for Ka-band. In this band, antenna arrays must employ large number of elements with appropriate beamforming techniques to combat the severe path loss. The goal of this paper is to analyze massive antenna arrays under realistic considerations for the use in terrestrial backhaul links. This analysis addresses practical issues from the implementation point of view...
Future 5G backhaul networks in dense small cell deployments will require high gain antennas with beam- and null-steering capabilities. In this framework this paper analyzes the null-steering capabilities of reflectarray antennas, as a low cost alternative to traditional antenna arrays. In particular, a random search algorithm is used to show that null-steering can be performed even with 1-bit reflectarrays,...
The concept of passive RFID tag-to-tag communications has been recently introduced and opens new promising perspectives, especially in the field of Internet-of-Things. In this paper, a simulation framework is proposed as a new tool allowing the performance evaluation of tag-to-tag radio links. The modeling takes into consideration the external source supplying the communication between tags, radiating...
This paper presents some of our antenna activities in the TT&C, GNSS and Data-Downlink area. Our involvement in such antenna designs spans over a 40 year period starting in the mid 70ies, first within the antenna group at LM Ericsson and Saab Ericsson, and now at RUAG [3].
This paper deals with the design of a new reconfigurable beam antenna used to improve the efficiency of spatial telemetry links on Nano-Satellite. This agile beam antenna is not built on the well-known array concept: AESA (Agile Electronically Scanned Array) but using a new one [1] called ARMA (Agile Matrix Radiating Antenna); MARPEM in French.
This paper presents a novel deployable Ka-band antenna folding in a 1.5U (10×10×15cm3) stowage volume suitable for 6U (10×20×30cm3) class CubeSats. This antenna is designed for telecommunication and is compatible with the NASA's Deep Space Network (DSN) at Ka-band frequencies (uplink: 34.2–34.7 GHz and downlink: 31.8–32.3 GHz). Detailed simulations, considering all aspects of the circularly-polarized...
This paper presents a compact X-band antenna with an isoflux radiation pattern and circular polarization. It consists of a miniaturized helix antenna connected to a stripline circuit that provides a sequential rotation feeding. The antenna is arranged over a vertically corrugated ground plane and it has been optimized for a CubeSat 3U nano-satellite platform. Its design, manufacture and results are...
In this paper, a single-fed four-panel 4×1 patch array antenna operating at 2.43 GHz with switched beam capability is proposed. The design allows the beam to be switched between four discrete directions giving 360° coverage. The antenna beam is switched over the azimuth plane for Φ = 0°, Φ = 90°, Φ = 180°, and Φ = 270°. The beam control is achieved by using GaN-based HEMT SPDT switches. Only three...
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