Metasurfaces: From microwaves to visible

A new approach is proposed to reject certain bands within the passband of an ultra-wideband planar monopole antenna. The proposed approach that utilizes a mushroom-type electromagnetic-bandgap (EBG) structure is proven to be an effective way for band-notched designs. The approach has many advantages, such as notch-frequency tunability, notch-band width controllable capacity, efficient dual-notch design, and stable radiation patterns. Several design examples using conventional mushroom-type EBG and edge-located vias mushroom-type EBG are presented. The examples exhibit good bandstop characteristics to reject the wireless local-area network interference bands (5.2- and 5.8-GHz bands). Besides, the causes that lead to the discrepancies between the simulations and measurements are discussed.

UWB Band-Notched Monopole Antenna Design Using Electromagnetic-Bandgap Structures

The RF community has long been searching for the ideal switch since the birth of electronics, and it is defined as a device having virtually no insertion loss (Ron = 0 Ω) over a wide frequency range, very high isolation [off-state capacitance (Coff)] = 0 fF), extremely high linearity (IIP2 and IIP3 → infinite), medium- to high-power handling (100 mW to 1 kW), and no dc power consumption. Our entire RF infrastructure ecosystem, from communication system networks, to satellite systems, to wideband spectral analysis, to instrumentation and radar systems, uses a variety of switches for signal routing and control (attenuation, phase shifting, etc.). The ideal switch was achieved long time ago using electromechanical relays, and even after nearly 100 years, it is still the best RF switch ever made from an electrical perspective [1]. It has very low insertion loss (Ron <;1 Ω), very high isolation (Coff of few fF), very high linearity and high power handling (100 mW to 50 W). However, it is bulky, expensive, and has an average lifetime of few million cycles.

The Search for a Reliable MEMS Switch

A pattern-reconfigurable, low-profile, efficient, electrically small, near-field resonant parasitic (NFRP), Huygens source antenna is presented. The design incorporates both electric and magnetic NFRP elements. The electric ones are made reconfigurable by the inclusion of a set of p-i-n diodes. By arranging these electric and magnetic NFRP elements properly, a set of three Huygens sources are attained, each covering a 120° sector. Pattern reconfigurability is obtained by switching the diodes on or off; it encompasses the entire 360° azimuth range. A prototype was fabricated and tested. The numerical and experimental studies are in good agreement. The experimental results indicate that in each of its instantaneous states at $f_{0} = 1.564$ GHz, the antenna provides uniform peak realized gains, front-to-back ratios, and radiation efficiencies, respectively, as high as 3.55 dBi, 17.5 dB, and 84.9%, even though it is electrically small: $ka = 0.92$ , and low profile: $0.05~\lambda _{{\mathbf {0}}}$ .

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Low-Profile, Electrically Small, Huygens Source Antenna With Pattern-Reconfigurability That Covers the Entire Azimuthal Plane

In this letter, a compact coplanar-waveguide-fed single-layer printed antenna with an ultrawideband (UWB) rectangular monopole radiator etched with a half-elliptical slot is presented. Collaborating with the UWB radiator, two symmetrical open-circuit stubs are extended from the ground plane to jointly achieve an ultrawideband impedance match with a compact size. The proposed antenna is fabricated and tested in an anechoic chamber, showing an ultrawide operating frequency range from 3.7 to 10.1 GHz with a quasi-omnidirectional gain from 2.0 to 7.3 dBi. With the advantages of a reduced size, an improved voltage standing wave ratio (VSWR), and a monolayer configuration without any back ground plane, the proposed antenna can be used in a wide range of UWB applications.

A Printed Single-Layer UWB Monopole Antenna With Extended Ground Plane Stubs

A dedicated low profile antenna for geodesic applications is presented. This type of antenna requires mitigation of multipath signals to achieve sub-centimeter level of precision. Typically, bulky and heavy choke ring structures have been used to reduce the effects of multipath interference. The antenna presented here consists of a low temperature co-fired ceramic (LTCC) patch antenna immersed in an electromagnetic bandgap (EBG) substrate. The EBG substrate reduces the effects of multipath by blocking the propagation of surface waves. The result is an antenna showing good multipath rejection and a stable phase center. The advantage of printed EBG substrates is that they can be realized in a low-weight, low-price, and low-profile fashion. First prototypes have been manufactured and tested, and its performance has been compared to that of a more classical choke ring antenna.

Low Profile GALILEO Antenna Using EBG Technology

Phased array technology is becoming a commercially important market for mobile telecommunication applications, e.g. mobile satellite terminals. Such systems, either for maritime, aeronautical or land applications, must be able to receive satellite broadcasting services on-the-move. Multimedia is here the driving force to develop cost-effective compact commercial terminals, favourably for various classes of applications, such as general or customised broadcasting services, for example. Such terminals are of special interest to the automotive industry because the terminals currently on the market for such applications are still partly based on mechanical moving parts, thus maintenance intensive, heavy and bulky, and subject to G-forces. These properties are not very appealing to the automotive industry where car aesthetics are ever so important. Far more favourable are the fully electronically steerable solutions that can be very compact and have very low maintenance. However, one of the major limitations and biggest design challenges of this type of phased array systems is the relatively high price due to its electronic complexity. The NATALIA project (New Automotive Tracking Antenna for Low-cost Innovative Applications) funded by ESA, is investigating the possibility of realizing a compact cost-effective solution for a receive- only full electronically steerable antenna for cars in Ku-band. The key items for the design of this antenna system are not only low-cost but also small size (around 20 cm in diameter and a height of a few em's) so that the antenna can easily be integrated into or onto the structure of the car. Different concepts for the NATALIA antenna have been investigated such as RF-phase shifters in (M)MIC technology and different configurations of beam forming/switching networks, all evaluated with respect to complexity/costs, performance (G/T) and size, resulting into a first baseline design. (5 pages)

Design Considerations for Compact Mobile Ku-Band Satellite Terminals

In this paper, we present GaAs MMIC based reconfigurable RF MEMS impedance matching networks for highly integrated (potentially single-chip) frequency-agile LNAs and adaptive multi-band front-ends. Such GaAs MMIC based RF MEMS LNA matching networks have been realized with a frequency tuning range of 40% (10–16 GHz and 15–23 GHz, respectively) and 1–3 dB of in-band losses. Simulated tunable LNA results based on measured data of GaAs MMIC MEMS matching circuits (and simulated data of MEMS matching networks made on quartz) show the potential of achieving a high gain and low in-band noise figure over such wide tuning ranges.

RF MEMS and MMIC based reconfigurable matching networks for adaptive multi-band RF front-ends

This paper presents the results of the development of an active phased array antenna for Ku-Band Receive-only mobile satellite communications realised within the ESA-project NATALIA. The phased array antenna is designed for mobile satellite services and dedicated for automotive applications. An overview of the complete build-up will be provided as well as the current status of the multilayer Printed Circuit Board (PCB) designed for mass production and a dedicated MMIC-component responsible for the beam steering of the array. Finally, the results of the measurements of a proof-of-concept breadboard performed to validate the antenna will be illustrated.

Low cost Ku-band electronic steerable array antenna for mobile satellite communications

In this paper, we report on recent results obtained within a pan-European research effort aiming at a successful integration of RF MEMS switches in a GaAs MMIC foundry process technology. Testing and characterization of GaAs based MEMS switches and RF circuits show promising results with respect to switch cycling tests, micro-seconds switching times and the relatively low losses demonstrated up to millimetre-wave frequencies. Compact GaAs RF MEMS based phase shifters together with a possible packaging solution are also presented.

Rens Baggen

Papers

Low Profile GALILEO Antenna Using EBG Technology

Design Considerations for Compact Mobile Ku-Band Satellite Terminals

RF MEMS and MMIC based reconfigurable matching networks for adaptive multi-band RF front-ends

Low cost Ku-band electronic steerable array antenna for mobile satellite communications

Design, packaging and reliability aspects of RF MEMS circuits fabricated using a GaAs MMIC foundry process technology