High-permittivity Ceramic Substrate Research Articles

Frequency-Scanned Monopulse Antenna for RSSI-Based Direction Finding of UHF RFID Tags

A compact printed-circuit leaky-wave antenna is designed to synthesize frequency-scanned monopulse patterns in the UHF RFID band from 902 to 928 MHz. A high-permittivity ceramic substrate is used to maximize the angular scanning range in such a narrow band. Two operating modes, i.e., narrow-field and wide-field modes, can be chosen by properly selecting the frequency channels and antenna ports. This allows to adapt to different fields of view while maximizing the maximum reading distance, as demonstrated with a fabricated prototype.

A Novel Electrically Small Ground-Penetrating Radar Patch Antenna with a Parasitic Ring for Respiration Detection.

An electrically small patch antenna with a low-cost high-permittivity ceramic substrate material for use in a ground-penetrating radar is proposed in this work. The antenna is based on a commercial ceramic 915 MHz patch antenna with a size of 25 × 25 × 4 mm3 and a weight of g. The influences of the main geometric parameters on the antenna’s electromagnetic characteristics were comprehensively studied. Three bandwidth improvement techniques were sequentially applied to optimize the antenna: tuning the key geometric parameters, adding cuts on the edges, and adding parasitic radiators. The designed antenna operates at around GHz and has more than 40 MHz continuous dB bandwidth. In comparison to the original antenna, the and dB fractional bandwidth is improved by 1.8 times and 4 times, respectively. Two antennas of the proposed design together with a customized radar were installed on an unmanned aerial vehicle (UAV) for a quick search for survivors after earthquakes or gas explosions without exposing the rescue staff to the uncertain dangers of moving on the debris.

Novi dizajn minijaturnih SIV filtera na keramičkom supstratu za c-pojas

This article presents new structures and methods of design of miniature third-order substrate integrated waveguide (SIW) bandpass filters on a high-permittivity ceramic substrate for the C-band. The aim was to appraise the feasibility of such filters by using a 3D electromagnetic (EM) simulator. The substrate integrated waveguide (SIW) offers good quality factors and electrical performances compared with other planar techniques. Its integration capabilities and fabrication cost are other benefits that make it attractive. Ceramic material offer electrical properties suitable in designing of passive devices. High relative permittivity with low dielectric losses makes it possible to miniaturize passive components while exhibiting high temperature stability, which is an important selection criterion for a filter designed to equip the payload of a satellite. Three SIW filters were designed on a Trans-Tech ceramic substrate (thickness = 254 mm, er = 90, and tand = 0.0009) with drastic specifications for space application. The first filter is composed of three SIW resonators with direct coupling, the second is composed of three SIW resonators with a cross-coupling to create a transmission zero, and the third is composed of three SIW resonators with circular holes etched on the top of the metal layer to achieve a super-wide band. The obtained results for the proposed filters are presented, discussed, and compared with relevant published literature. The proposed filter can be used to enhance the performance of microwave devices used for C-band, especially Satellite communications.

Broadband <inline-formula> <tex-math notation="LaTeX">$E$ </tex-math> </inline-formula>-Band WR12 to Microstrip Line Transition Using a Ridge Structure on High-Permittivity Thin-Film Material

A rectangular WR12 waveguide to microstrip line (MSL) transition using a very thin high-permittivity ceramic substrate ( $\varepsilon _{r} = 9.9$ and $h = 127 \,\,\mu \text{m}$ ) is presented and analyzed. The proposed configuration uses a gradually extending metal ridge over a thin-film MSL to ensure electric field transformation, and an accurate impedance matching, while maintaining a good electrical contact, without any soldering or gluing. The fabricated prototype has been successfully tested in terms of insertion and return losses. The obtained results exhibit a bandwidth of more than 37% at −10 dB with an insertion loss of 1.5–2.7 dB, over the entire 60–90-GHz frequency band. The design simplicity and suitability for high-permittivity thin-film substrates, as well as the very broadband operation capability, enable it to be easily integrated with various planar monolithic microwave integrated circuits/miniaturized hybrid microwave integrated circuits microstrip circuits for different millimeter-wave applications.

A 60‐GHz multi‐beam antenna array design by using MHMICs technology

ABSTRACTThe integration feasibility of two technologies including Miniaturized Hybrid Microwave Integrated Circuit (MHMIC) and Printed Circuit Board (PCB) are experimentally demonstrated at millimeter wave frequencies through the design of a switched beam antenna array. A 1 × 4 array of aperture coupled patch antennas etched on a RO5880 substrate is fed by a 4 × 4 butler matrix etched on a piece of high permittivity ceramic substrate. By using the proposed combined fabrication technologies, the feeding part on the ceramic substrate can be easily integrated with MMIC active component, while the radiation part is individually improved. Comparison of simulated and measured results show that the proposed switched beam antenna offers a −10 dB matching bandwidth of 6 GHz ranging from 58 GHz to 64 GHz and a multi beam radiation pattern which is focused in 45°, 15°, −15°, −45° directions. © 2016 Wiley Periodicals, Inc. Microwave Opt Technol Lett 58:1844–1847, 2016

Characterization and Implementation Methods of Multilayer Inductors with Ni-Zn Ferrite and Carbonyl SF Powder Iron on Ceramic Substrates for RF Amplifers

Characterization and implementation of multilayer inductors constructed with Ni-Zn ferrite and Carbonyl SF powder iron on ceramic substrates for radio frequency (RF) power amplifier applications are presented for the first time. The multilayer inductor has a base material with high permittivity and low loss ceramic substrate, which has spiral inductor configuration and overlay magnetic substrate that is used to increase the effective permeability of the multilayer structure. High permittivity and low loss ceramic substrate gives the inductor a lower profile and better thermal performance for radio frequency applications. Ni-Zn ferrite and Carbonyl SF powder iron magnetic layers are used as an overlay magnetic substrate to increase effective permeability of the multilayer structure where magnetic flux flows through without degrading the performance of the inductor. The multilayer inductors that are designed are used as resonator inductor in the load line, RF choke, and combiner output inductor for RF power amplifiers carrying a large amount of current. Several different multilayer inductors are simulated, implemented, and measured. Various characteristic curves such as quality factor, inductance, resonance, return loss, and impedance versus frequency for different permeability and thickness of the magnetic substrate using Ni-Zn ferrite and powder iron core are measured, simulated, and presented. Measured and simulated results have been compared and found to be close. The multilayer inductors are then integrated to the RF amplifier, and the amplifier is tested for performance when it is interfaced with matched load at the rated power. It has been shown that the proposed multilayer inductor design can be used for radio frequency amplifier applications when high current flow and lower profile are required.

Thin bandpass filters containing sections of symmetric strip transmission line

Thin (1-mm thick or thinner) combline bandpass filters based on sections of symmetric strip transmission lines and containing closely spaced (0.1–0.2 mm apart) stepped-impedance resonators are described. It has been found that, if these filters are made on high-permittivity ceramic substrates, their dimensions prove to be smaller than the dimensions of other ceramic-based filters. Various frequency characteristics of these filters—symmetric, with increased one-sided selectivity, and with a constant delay time—have been analyzed. The experimental results obtained for a 1-mm-thick bandpass filter with ɛ r = 9.7 are in good agreement with the computer-simulation data.

Miniaturization of ring resonator bandpass filters using dielectric ceramic substrates

A compact bandpass filter is designed using stepped impedance ring resonators with zero-degree feed structure.This compact bandpass filters using FR4 and high-permittivity ceramic substrates (with respective dielectric constants of 4.5 and 13.46) are investigated. Using high Q, high permittivity dielectric ceramic materials as substrates, the filters demonstrate high selectivity, compact size, and can be applied in several microwave communication systems. An electromagnetic simulator is used to design the ring resonators, and to calculate the coupling coefficient of the basic coupling strictures. A precise planar bandpass filter with ceramic substrates has been fabricated using the screen printing technique. The responses of bandpass filters using FR4 (er = 4.5, tan δ = 0.015) and Mg4Nb2O9 with 0.75 wt% Fe2O3 (er = 13.46, tan δ = 0.00004) ceramic substrates are designed at a center frequency of 2.4 GHz with bandwidth of about 9%. The compact size, low-loss, and performance of the filter are demonstrated in this article. © 2012 Wiley Periodicals, Inc. Microwave Opt Technol Lett 55:660–663, 2013; View this article online at wileyonlinelibrary.com. DOI 10.1002/mop.27346

Two-poles compact microstrip bandpass filter with sharp transition bands using high permittivity substrate

This article describes the two-pole microstrip band-pass filters using miniaturized center-stubbed open stubs and tapped-line input/output ports. The two-poles bandpass filters by using FR4 and high-permittivity ceramic substrates (with respective dielectric constants of 4.5 and 31.55) are investigated. Microwave dielectric ceramics with high permittivity are commonly applied in several microwave communication components. The advantage of using high permittivity ceramic substrates is to reduce the sizes and increase the performance of microstrip bandpass filters. The responses of the filters using FR4 (er = 4.5, tan δ = 0.015) and Nd(Zn1/2Ti1/2)O3 (er = 31.55, tan δ= 0.00005) ceramic substrates are designed at a center frequency of 2 GHz. The compact size, low-loss, sharp response, and performance of the filter are presented in this article. © 2012 Wiley Periodicals, Inc. Microwave Opt Technol Lett 54:1683–1686, 2012; View this article online at wileyonlinelibrary.com. DOI 10.1002/mop.26889

Band-pass filters using high-permittivity ceramics substrate

The miniaturization of ring band-pass filters by employing high-permittivity ceramic substrates (with respective dielectric constants of 9.7 and 23.5) are investigated. Microwave dielectric ceramics with high-permittivity are commonly applied in several microwave communication components. With the advantages of compact size, high-permittivity ceramics can be used as the substrate for band-pass filters. Moreover, the fundamental characteristics of newly developed compact ring resonators have also been described and applied to the design of band-pass filters. In this article, the designed ring resonators structures are simulated using an HFSS simulator. The responses of the fabricated band-pass filters using Al2O3 (εr = 9.7, tanδ = 0.0001) and 0.875Mg0.95Zn0.05TiO3-0.125Ca0.8Sm0.4/3TiO3 (εr = 23.5, tanδ = 0.000083) ceramic substrates are designed at the center frequency of 2.4 GHz. This compact size, low loss band-pass filter should be useful in many wireless communication systems. © 2010 Wiley Periodicals, Inc. Microwave Opt Technol Lett 52:2344–2347, 2010; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/mop.25439

Wavefront formation using modal liquid-crystal correctors

Results of experiments on wavefront formation using multichannel modal correctors in an adaptive optical system with feedback are reported. Two types of correctors, one based on a glass substrate with a high-resistance layer deposited onto it and the other based on a high-permittivity ceramic substrate, are developed and investigated. The results show that it is expedient to use the correctors in applications that do not require a high speed of response.

Microstrip ring resonator bandpass filters using ceramic substrate

AbstractThe miniaturization of ring bandpass filters by employing high‐permittivity ceramic substrates (with respective dielectric constants of 9.7 and 23.5) are investigated. Microwave dielectric ceramics with high permittivity are commonly applied in several microwave communication components. With the advantages of compact size, high‐permittivity ceramics can be used as the substrate for bandpass filters. Moreover, the fundamental characteristics of newly developed compact square‐ring resonators have also been described and applied to the design of bandpass filters. In this paper, the designed square‐ring resonators structures are simulated using an IE3D simulator. The responses of the fabricated bandpass filters using Al2O3 (εr = 9.7, tan δ = 0.000036) and 0.875Mg0.95Zn0.05TiO3‐0.125Ca0.8Sm0.4/3TiO3 (εr = 23.5, tan δ = 0.000021) ceramic substrates are designed at the center frequency of 2.4 GHz. This compact size, low loss bandpass filter should be useful in many wireless communication systems. © 2009 Wiley Periodicals, Inc. Microwave Opt Technol Lett 52: 218–220, 2010; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/mop.24847

Investigation of Microwave Properties of High Permittivity Ceramic Substrate

The study of new compositions of high permittivity dielectric materials at microwave frequency is proposed in this paper. New types of dielectric materials will be developed, measured and implemented into working electrical microwave models with the help of microwave simulation software. After fabrication, the performance and characteristics of these materials will be studied and a comparison will be made in order to find the most effective material and design for use in real world microwave devices and designs. A simple dielectric resonator structure will then be developed to simulate the use of the new dielectric material in future microwave applications.

Using high permittivity ceramic substrates to fabricate a miniaturized bandpass filter with capacitive load

AbstractUsing high permittivity ceramic substrates and capacitive coupling to miniaturize the sizes of Butterworth bandpass filters are investigated. The selectivity and stopband rejection of the designed filters can be improved significantly by utilizing a skew‐symmetric (zero degree) feed structure. These factors result in reducing the size of the filter. The responses of the Butterworth filters using Al2O3 (εr = 10, Q × f = 20,000 GHz) and 0.85(Mg0.95Zn0.05)TiO3 − 0.15Ca0.6La0.8/3TiO3 (εr = 26, Q × f = 86,000 GHz) ceramic substrates are designed at a center frequency of 2.4 GHz. The compact size, low‐loss, sharp response, and performance of the filter are presented in this article. © 2007 Wiley Periodicals, Inc. Microwave Opt Technol Lett 49: 1609–1613, 2007; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/mop.22533

Using high permittivity ceramic substrates to design a bandpass filter with open stub

AbstractThe advantage of using high permittivity ceramic substrates is to miniaturize the sizes of microstrip bandpass filters. The selectivity and stopband rejection of the designed filters can be improved significantly by utilizing open stubs. The designed filter with appropriate open stub can create tunable transmission zero. These factors will reduce the size of the filter and increase its performance. The responses of the filters using Al2O3 (εr = 9.8, tanδ = 0.0001) and 0.96(Mg0.95Zn0.05) TiO3‐0.04SrTiO3 (εr = 20.7, tanδ = 0.00007) ceramic substrates are designed at a center frequency of 2.45 GHz. Finally, the open stub and high permittivity ceramic substrates are applied to the design of a direct‐coupled hairpin filter. The compact size, low‐loss, sharp response, and performance of the filter are presented in this article. © 2007 Wiley Periodicals, Inc. Microwave Opt Technol Lett 49: 771–773, 2007; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/mop.22252

A planar multicell structure for advanced integrated reactive power modules

An alternative approach to construct a planar integrated reactive power module is presented in this paper. Enclosed in a planar core, a few copper strips plated on both sides of a high-permittivity ceramic substrate generate a series of so-called L-C cells. Various equivalent circuits may be realized with this chip-like module using different printed circuit board PCB interconnections between the L-C cells. The experimental results show its potential as an integrated high-frequency power resonator. Good correspondence between experimental measurement and first-order models is demonstrated.

Bandwidth enhancement of U‐slot patch antenna on high permittivity ceramic substrate for Bluetooth application

AbstractA patch antenna on a very high‐permittivity ceramic substrate with a pair of U‐shaped slots is investigated experimentally at 2.45 GHz. The dielectric constant of the ceramic substrate is 43. By embedding a pair of U‐shaped slots close to the nonradiating edges of the patch, two adjacent resonant modes are very close to each other and are both covered. Thus, an enhanced impedance bandwidth of 5.3% can be achieved. The proposed antenna operates with 2:1 VSWR throughout the entire Bluetooth band (2400–2484 MHz). Details of the antenna design and experimental results are presented. © 2003 Wiley Periodicals, Inc. Microwave Opt Technol Lett 36: 499–501, 2003; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/mop.10802

An experimental study of microstrip antennas on very high permittivity ceramic substrates and very small ground planes

An experimental study of rectangular microstrip antennas on two ceramic composite substrates, barium-titanate with a dielectric constant of 37 and neodymium-titanate substrates with a dielectric constant of 85, is presented. The measured results for radiation patterns, cross-pol levels and resonant frequencies for antennas with ground planes as small as 1"/spl times/1" are given. It is shown that, for very small ground planes, the far-field pattern is smooth and nearly omnidirectional in both E and H planes, a feature that may be of interest in many mobile applications.

Microstrip antenna with lossy patch

A high-permittivity ceramic substrate was used to reduce the microstrip antenna dimension on patch size as compared with a conventional low-permittivity substrate. A lossy conductive patch was studied for broadening the bandwidth. Here, experiments on single-feed circularly polarized (CP) microstrip antennas for global positioning system (GPS) applications are demonstrated. Results of the Smith charts, axial ratios, and radiation patterns are measured and discussed. © 1998 John Wiley & Sons, Inc. Microwave Opt Technol Lett 18: 228–230, 1998.

Miniature microwave filters for communication systems

This paper presents new developments in miniature integrated microwave filters suitable for application in mobile communication handsets, wireless LAN's and microwave fixed links. Recent measured results for active microwave filters are presented with emphasis on their nonlinear behavior. The use of high permittivity ceramic substrates in parallel plate TEM mode stripline filters is described and recent measured results are presented for a prototype 2-GHz filter occupying a volume of 0.5-cubic centimeters. E-Plane filters for millimeter wave applications are discussed and measured results are presented for a novel E-Plane filter with asymmetric frequency response which was realized in a planar structure. Finally, a new type of ceramic loaded E-Plane filter is proposed. >