Bo Pan

• Harbin Institute of Technology

A reliable numerical model is developed to predict the deformation of mismatch and normal butt-welded joints after laser and gas metal arc hybrid welding (Laser-GMAW). A smaller deflection is produced in the mismatch joint as a result of a more uniform weld profile along the thickness direction, while a larger shrinkage deformation is obtained as a...

A turbine component with 130 blades requests high dimensional precision to ensure the assembly requirements. The dimensional precision is significantly influenced by welding distortion. In this research work, welding distortion in the turbine component by electron beam welding was predicted through elastic finite element method based on inherent st...

The development of polarisation-reconfigurable antenna arrays on multilayer liquid crystal polymer (LCP) technology for remote sensing applications is presented for the first time. Two 2×2 antenna arrays operating at 14 and 35 GHz have been designed, fabricated and measured. These arrays use printed patch antenna elements and can operate in two lin...

This paper presents a radio-frequency (RF) evanescent-mode cavity resonator for passive wireless sensor applications. The evanescent-mode resonator is composed of a cavity with a center post. The resonant frequency of the resonator is determined by the dimension of the cavity, the gap between top membrane electrode of the cavity, and the center pos...

A printed dipole with an integrated balun features a broad operating bandwidth. The feed point of conventional balun structures is fixed at the top of the integrated balun, which makes it difficult to match to a 50-Omega feed. In this communication, we demonstrate that it is possible to directly match with the 50-Omega feed by adjusting the positio...

Two types of broadband end-fire antennas are developed for sectorized coverage of 60-GHz wireless personal area networks (WPAN) applications. The first one is an integrated horn antenna in RO4000 laminates. Using the combination of through-, blind-, and buried-vias, a horn structure with both E- and H-plane flares can be mapped into a multilayer la...

An integrated horn antenna is presented for 60-GHz WPAN applications. Compared with other types of antenna for 60-GHz WPAN applications, an integrated horn antenna features wide bandwidth and high gain. This integrated H-plane horn is elevated on the top of the substrate using CMOS-compatible microfabrication steps. Antenna efficiency is greatly im...

A triple-band low-profile planar antenna is developed for wireless applications. The triple-band planar antenna consists of a two-strip monopole for the 2-GHz band, a horizontal monopole for the 3.5-GHz band, and a vertical monopole for the 5-GHz. The planar antenna is printed on a very thin substrate (0.254 mm in thickness) with a very low profile...

A printed dipole with an adjustable integrated balun is presented, featuring a broadband performance and flexibility for the matching to different impedance values. As a benchmarking topology, an eight-element linear antenna array is designed and built for base stations used in broadband wireless communications.

In this paper, the propagation characteristics of an enhanced-thickness magnetic nanoparticle thin film are investigated on high resistivity silicon substrate (10,000 ohm - cm) for the first time up to 60 GHz. Contrary to other thin films, this nanoparticle thin film can achieve a thickness up to several hundred nanometers, even to micron. The enha...

This paper presents an RF airflow sensor based on an evanescent-mode cavity resonator. The frequency loading is achieved by a capacitive post in the center of a cylinder cavity. As a sensing mechanism, an elastic membrane with a sensing beam is utilized to generate a strain on the top of the cavity. The airflow deflects the sensing beam, changing t...

This paper presents a novel surface micromachined low-loss integrated cavity filter with a pair of transmission zeros using a simple source-load coupling scheme for emerging 60 GHz applications. The proposed method eliminates the dielectric loss by elevating the cavity-based filter into the air with the aid of the polymer-core conductor surface mic...

A new low-profile broadband dual-frequency planar antenna is developed for wireless handsets. The dual-frequency antenna consists of a two-strip monopole for the 2-GHz band and a planar monopole for the 5-GHz band. The developed antenna features a low profile due to the introduction of an S-strip and a T-strip which are separately printed on the tw...

A single-feed circular microstrip antenna with reconfigurable polarization capability is proposed. This antenna has a simple structure, which consists of a radiating circular patch, five switches (PIN diode), three matching stubs, and a 50 microstrip feed line. It can be switched between 4 different states: two states (low-frequency and high-freque...

A cavity-backed loop antenna is developed for producing broadband circularly polarized (CP) radiation. The antenna configuration consists of a slot loop and a strip loop. The slot loop radiates a CP wave at a lower frequency while the strip loop produces CP radiation at a higher frequency. A combination of the two frequencies leads to a bandwidth e...

This paper demonstrates a novel coplanar waveguide (CPW) to rectangular waveguide (RWG) transition and its application as an integration enabling structure for filters at W-band for the first time to the best of the authors' knowledge. In the proposed wideband transition, the CPW and RWG are integrated on one side of the substrate, while the coupli...

In this chapter, we briefly introduce the exciting advances in MEMS-integrated antennas with reconfigurability, as well as several high performance millimeter antennas created using modern micromachining technologies. There are lots of excellent designs in this area. However, we can only select several examples to represent the current state-of-the...

In this letter, a 3D high-quality-factor millimeter- wave cavity resonator is integrated on the lossy soda-lime glass substrate utilizing surface micromachining technologies. With a height of 300 mum, the air-lifted cavity features a measured Q of at least 219 at 30 GHz, demonstrating an improvement by almost an order of magnitude with respect to r...

A new type of low-profile broadband planar antenna is developed for DVB-H, DCS-1800, and IMT-2000 handsets. The planar antenna for UHF-band DVB-H terminals has a height of 8 mm while the antenna height for DCS-1800 and IMT-2000 applications is only 4.8 mm which is much lower than previously published antenna configurations. The broadband planar ant...

In this paper, novel U-slot and Yagi-Uda micromachined patch antennas were designed based on the "micromachined elevation " technique to improve the performance of mm-wave cognitive radios in terms of gain, weight and bandwidth. The elevated antennas were fed with a micromachined probe connected to a CPW line on top of a high - substrate. By elevat...

A novel fully micromachined coplanar waveguide (CPW) to rectangular waveguide transition is presented in this paper. A metalized probe is adopted to couple the signal from the CPW to the rectangular waveguide through an aperture located at the center of the bottom broad wall of the rectangular waveguide. The transition was optimized using HFSS 10 o...

A low-profile planar antenna has been developed for UHF-band DVB-H terminals. The antenna has a height of 8 mm and can be easily integrated with a printed circuit board. Through the exploitation of the electromagnetic coupling between a T-strip and an S-strip, the antenna can radiate efficiently over a wide frequency band. It has been demonstrated...

Two novel broadband low-profile antennas are developed for the mobile terminals of wireless applications. The first one is a quasiplanar antenna which has a height of 0.06lambda₀, where lambda₀ is the free-space wavelength at the centre frequency. The second one is a planar antenna which has a height of 0.056lambda₀...

A very-low-profile (VLP) broadband planar antenna is developed for DCS-1800 and IMT-2000 handsets. The VLP planar antenna consists of an S-strip and a T-strip, which are separately printed on the two sides of a thin substrate. The antenna height is only 4.8 mm which is much lower than previously published antenna configurations. The VLP planar ante...

A broadband low-profile monopole antenna is analyzed by using balanced and unbalanced mode decomposition. The broadband antenna consists of an S-strip and a folded T-strip that are separately printed on the two sides of a thin planar substrate, forming a two-strip monopole. The two-strip antenna can achieve a bandwidth (VSWRles2) of ~40% with a hei...

A cavity-backed loop antenna with a simple feeding structure is proposed for broadband circularly polarized (CP) radiation. The proposed antenna configuration consists of a slot loop and a strip loop. The slot loop radiates a CP wave at a lower frequency while the strip loop produces CP radiation at a higher frequency. A combination of the two freq...

A novel type of low-profile broadband and dual-frequency monopole antennas is developed for wireless applications. The broadband monopole consists of an S-strip and a folded T-strip which are separately printed on the two sides of a thin planar substrate. No via process is involved in the fabrication. The two-strip planar monopole can achieve a ban...

This paper presents several novel 3D antennas topologies that feature the capability of substrate-independent integration for future mm-wave systems. The high-aspect-ratio surface micromachining technology has been utilized to implement these 3D structures. A 100 GHz vertical Yagi-Uda antenna is fabricated and tested for end-fire radiation applicat...

This paper reports two system-on-package (SoP) integration schemes for utilizing the Yagi-Uda antenna in the RF/microwave/millimeter wave applications. A substrate independent W-band vertical Yagi-Uda was fabricated and characterized. It shows a forward gain of 5.3 dBi and a front-to-back ratio of 6 dB and has proven the feasibility of using the su...

A vertical W-band surface-micromachined Yagi-Uda monopole array is proposed and implemented for the first time. The monopoles stand on a high-k soda-lime glass substrate and are fed by a coplanar waveguide. The geometry functions as a vertically placed Yagi-Uda antenna due to the image theory. The performance of the vertical Yagi-Uda is to be super...

A broadband elevated microstrip coupler has been designed and implemented on the soda-lime glass with surface micromachining technology. The coupler is elevated by 200 μm and fed by a combination of epoxy-core metal post and coplanar waveguide, which helps eliminate the conventional air/dielectric interface problems. By this method, frequency dispe...

This paper reports various three-dimensional (3-D) surface micromachining technologies and their successful application to a variety of millimeter-wave antennas. Contrary to conventional planar type printed-circuit antenna structures, the 3-D surface micromachined structures described here minimize substrate effects, enabling substrate independence...

In this paper, an air-filled elevated microstrip antenna resonating at 25 GHz based on surface micromachining technology is fabricated and characterized for the first time. The antenna is air-lifted on high-epsi_r soda-lime glass substrate and demonstrates a 7% 10 dB bandwidth in measurement. A 10.2 dBi directivity and a nearly frequency-...

A W-band CPW-fed 3-D quarter-wavelength monopole that is vertically mounted on a variety of substrates is reported for the first time. A transition from coplanar waveguide to vertical coaxial structure is investigated. The structure demonstrates broadband impedance matching and symmetry radiation pattern in W-band. Greater than 10 dB return loss ov...

RF MEMS based on epoxy-core conductors were demonstrated previously (1) for simple passive elements such as inductors. In this work, the work of (1) is extended to radiating structures. Increases in operation frequencies have reduced required RF radiator sizes, while simultaneously advances in 3-D fabrication technology have increased achievable th...