A5041001776- Antenna Design and Analysis
- Microwave Engineering and Waveguides
- Advanced Antenna and Metasurface Technologies
- Ferroelectric and Piezoelectric Materials
- Microwave Dielectric Ceramics Synthesis
- Additive Manufacturing and 3D Printing Technologies
- Electromagnetic wave absorption materials
- Advanced Sensor and Energy Harvesting Materials
- Microwave and Dielectric Measurement Techniques
- Antenna Design and Optimization
- Photonic and Optical Devices
- Energy Harvesting in Wireless Networks
- Photonic Crystals and Applications
- Advanced ceramic materials synthesis
- 3D IC and TSV technologies
- Advanced Materials and Mechanics
- Luminescence Properties of Advanced Materials
- Dielectric materials and actuators
- Wireless Body Area Networks
- Engineering and Test Systems
- Multiferroics and related materials
- Metamaterials and Metasurfaces Applications
- Acoustic Wave Resonator Technologies
- Manufacturing Process and Optimization
Loughborough University
2016-2020
University of Leeds
2002-2003
A cold sintering process (150 °C, 30 min and 200 MPa) was employed to fabricate Na0.5Bi0.5MoO4–Li2MoO4 (NBMO-LMO) composites with up 96.4% relative density. X-ray diffraction traces, backscattered electron images Raman spectra indicated the coexistence of NBMO LMO phases in all no detectable secondary phases. The pemittivity (εr) temperature coefficient resonant frequency (TCF) decreased, whereas microwave quality factor (Q × f) increased, increasing weight % LMO. Near-zero TCF obtained for...
This article presents the designs of ultrawideband microwave flat gradient index (GRIN) lenses, which realizes over a 108% fractional bandwidth (12-40 GHz). The frequency-independent ray optics method is employed to determine radially varying permittivity profile lenses. challenge realizing such and limitations in dielectric material choices are overcome by two additive-manufacturing-aided approaches: 1) partially infilled dielectrics with varied periodicity, ensures lens performance at...
Fused filament fabrication (FFF) is a well-known and greatly accessible additive manufacturing technology, that has found great use in the prototyping manufacture of radiofrequency componentry, by using range composite thermoplastic materials possess superior properties, when compared to standard for 3D printing. However, due their nature synthesis, they are often challenge print successfully which turn affects microwave properties. Hence, determining optimum printing strategy settings...
Dense (Bi0.95Li0.05)(V0.9Mo0.1)O4-Na2Mo2O7 (100-x) wt.% (Bi0.95Li0.05)(V0.9Mo0.1)O4 (BLVMO)-x Na2Mo2O7 (NMO) composite ceramics were successfully fabricated through cold sintering at 150 °C under 200 MPa for 30 min. X-ray diffraction, back-scattered scanning electron microscopy, and Raman spectroscopy not only corroborated the coexistence of BLVMO NMO phases in all samples, but also absence parasitic interdiffusion. With increasing concentration, relative pemittivity (εr) Temperature...
Additive manufacturing (AM) has become more important and common in recent years. Advantages of AM include the ability to rapidly design fabricate samples much faster than traditional processes create complex internal geometries. Materials are crucial components microwave systems proper accurate measurement their dielectric properties is aid a high level accuracy design. There numerous techniques finding most appropriate method requires consideration all different factors limitations. One...
Additive manufacturing (AM) of co-fired low temperature ceramics offers a unique route for fabrication novel 3D radio frequency (RF) and microwave communication components, embedded electronics sensors. This paper describes the first-ever direct printing ceramics/floating electrode structures. Slurry-based AM selective laser burnout (SLB) were used to fabricate bulk dielectric, Bi2Mo2O9 (BMO, sintering = 620–650°C, εr 38) with silver (Ag) internal floating electrodes. A printable BMO slurry...
The additive manufacturing process of multimaterial extrusion offers performance advantages using functional materials including conductors while making accessible the third dimension in design electronics. In this work, we show that additional geometrical freedom offered by technique can be exploited for and realization filters made 3-D resonators exhibit enhanced characteristics. coupling properties grounded square split ring (SRRs) are initially explored. We demonstrate simulations...
The world's first additively manufactured dielectric loaded profiled conical horn antenna is presented in this letter. With a smooth flare and two core materials, offers symmetrical patterns, wideband gain, low sidelobe level, cross polarization. Additive manufacturing, including electroplating, has been employed to address the fabrication challenges. measurement results show that process produces with reduced mass volume (<;200 g three-dimensional-printed flange) high performance realized...
This paper presents several demonstrators that utilize advanced additive manufacturing (AM) to rapidly prototype antennas, RF components for microwave and mm-wave applications. Antenna substrates with tailored permittivity; lenses, reflectarray locally varied dielectric properties; metamaterials can be fabricated by using extrusion based AM processes such as fused filament fabrication method realize high gain antenna systems low material cost, time-saving impact the environment.
This paper describes a novel method of characterizing complex permittivity using complementary frequency selective surface (CFSS). The CFSS provides passband behavior and the change in when material under test (MUT) is placed adjacent to has been used for retrieving MUT. MUT are determined based on measured bandpass resonant insertion loss with an amplitude-only where phase measurements not required. technique offers convenient, fast, low-cost nondestructive measurement that restricted by...
This paper explores advanced additive manufacturing for creating RF circuits and componentry analyses their performance. Additive manufacture of such objects allows novel complex structures to be fabricated realize high gain antenna systems with low material costs, reduced manual fabrication impact on the environment. Furthermore, it currently offers performance that can competitive through further advances in processes materials.
Utilization of advanced additive manufacturing for RF applications has received a great deal attention due to the potential reduced costs and greener processes. This paper presents different contributions that use extrusion based technology in fabricating components including reflectarrays, lenses, multi-material artificial dielectrics waveguide sections. intends disclose challenges facing industrial public acceptance this as well opportunities.
A novel optically controlled one dimensional (1D) photonic bandgap (PBG) microstrip structure is proposed. This device consists of a 50 /spl Omega/ transmission line and PBG ground plane both deposited onto photoconductive substrate. With no optical illumination the exhibits well-defined stopband. When light focused through holes in substrate, electron-hole pairs are generated to form photoinduced plasma. increases conductivity exposed region substrate forms complete plane. The then acts as...
This paper presents several demonstrators that utilize advanced additive manufacturing to rapidly prototype antennas, RF components for microwave and mm-wave applications. Antenna substrates with tailored permittivity; lenses, reflectarray locally varied dielectric properties; metamaterials can be fabricated by using the fused filament fabrication method realize high gain antenna systems low material cost, time-saving impact environment.
In this research, stereolithography (SLA) based additive manufacturing (AM) has been investigated as a fabrication method for producing artificial dielectrics. Initially, the effect of curing time on microwave electromagnetic properties (X-band) photoinitiated resin used was measured and found to be negligible after 15 minutes UV curing. Artificial dielectric isotropic anisotropic lattice structures were then designed fabricated, allowing varying permittivity between 1.23 2.80 through...
This study considers a wideband monopole antenna and its interactions with different separations from the human body phantom over wide frequency. A meshed alternative version has also been developed which similar performance to circular but requires less material. The specific absorption rate efficiency of this have analysed as function separation distance mesh design fabricated by using embroidery 3D printing techniques.
The optical control of a microstrip one dimensional (1-D) photonic bandgap (PBG) structure has been demonstrated over the frequency range 7-13GHz. A PBG was fabricated on Duroid 6010 and high resistivity photoconductive Si wafer placed in contact with ground plane. With no illumination incident upon Si, filtering properties are well-defined. When is illuminated suppressed. Under experimental results display an increase S/sub 21/ 6.5dB reduction 11/ more than 8dB at centre 10GHz. Experimental...
In this work, we present an offset-fed metal-only reflectarray design utilizing a 3D phasing element, namely 3D-cross, to achieve the phase shift coverage of up 360°. This is suitable for space applications which use dielectrics not desirable. The presented herein points beam in direction normal reflectarray, with illumination from feed horn incident at skew angle 30°. simulated gain normal-directed found be 28.9 dBi 35.6GHz. aperture efficiency 47%, while sidelobe level -19.7dB, relative main lobe.