Cheng-Hung Lin

Bio: Cheng-Hung Lin is an academic researcher from HTC. The author has contributed to research in topics: Antenna measurement & Radiation pattern. The author has an hindex of 4, co-authored 4 publications receiving 23 citations.

The 3D Far-Field Antenna Measurement Technology for Radiation Efficiency, Mean Effective Gain and Diversity Antenna Operation

Abstract: In this paper, facilities of antenna measurement have recently commissioned a spherical far-field measurement system The low profile far-field spherical scan system provides significant advantages over the older far-field testing including elimination of problem of simple theta (thetas) and phi (phi) rotary axis with indoor far-field range testing, complete measurement characterization of the antenna, and improved accuracy The mobile phone under test of far-field range testing has been the plan at the Cellular Telecommunications & Internet Association (CTIA) certification program test requirements for performing radiated power and receiver performance measurement This paper will discuss the antenna and wireless system integration tested with the TRP/TIS and spherical antenna measurement for far-field system The spherical far-field antenna system applied to total radiation efficiency, mean effective gain (EMG) and diversity gain measurement and applications

The Omni-directional Dipole Antenna Structure and Design

Abstract: The design relates generally to the field on antennas and more specifically, to a low profile linear polarized H-shape dipole antenna. The antenna includes a printed circuit board that has a dielectric substrate provided with H-shape face and one dipole element formed on the dielectric substrate. The printed circuit board is also provided with a balance to unbalanced feed network that is operatively connected to the H-shape dipole arm element. In this design, the H-shape dipole antenna fed network with tapered balun is studied. The design and experimental results of low profile microstrip planar dipole antenna with tapered balun shows fairly good performances in this paper. The feed network of the design with wider bandwidth and lower power loss tapered microstrip line to overlap coplanar stripline (CPS) transition that provided unbalanced to balanced line with balanced equal power output of phase. The achieved planar dipole antenna exhibits 421 MHz for VSWR = 2 bandwidths. Full-wave EM analyses shows good agreement with those experimental data.

The Tapered TEM Horn Antenna Design for EMC and Radiation Measurement

Abstract: The semi-rigid cable for microwave band as a feeding network structure that effectively excited tapered TEM horn antenna geometry is proposed. The semi-rigid cable to parallel waveguide transition then to fed tapered TEM horn antenna. The designed tapered TEM horn antenna has the merits such as wideband, simple feeding network, low profile compact size with fairly good antenna performances such as return loss, peak gain and radiation patterns.

The Pliant Monopole Antenna (PMA) Design for Handset Phone Operation

Abstract: This paper proposes a new antenna technique for pliant monopole antenna (PMA) as a radiator. This branch meander lines PMA based on two asymmetric meander lines with flexible structure exhibits good performances. Branch lines PMA radiator has the merits to improve antenna bandwidth with fine frequency tuning. The design bandwidth full cover 820 MHz~960 MHz and 1700~1990 MHz The PDA phone for GSM, EGSM, DCS, PCS, CDMA and CDMA2000 applications is well demonstrated with the integration and measurement of the co-designed PMA.

340 GHz On-Chip 3-D Antenna With 10 dBi Gain and 80% Radiation Efficiency

Abstract: This paper discusses the design methodologies of a 340 GHz on-chip 3-D antenna. Firstly, a high-gain and high-radiation efficiency substrate integrated waveguide (SIW) cavity backed on-chip antenna is designed using a standard 0.13- $\mu{\hbox{m}}$ SiGe BiCMOS technology. Then, a low-permittivity supporter and a dielectric resonator (DR) are vertically stacked on the proposed on-chip antenna, forming a 3-D Yagi-like antenna to further enhance the gain and radiation efficiency. The measurements showed that the proposed antenna achieved a peak gain of ${\sim}$ 10 dBi and radiation efficiency of ${\sim}$ 80% at 340 GHz; the impedance bandwidth is ${\sim}$ 12% with the use of dielectric resonator antenna (DRA) and the Yagi-like structure. The antenna size is ${\sim} {\hbox{0.7}}\times {\hbox{0.7}}\ {\hbox{mm}}^{2}$ .

Yet another antenna efficiency measurement method in reverberation chambers

Abstract: Radiation efficiency is one of the most difficult to measure quantities of antennas. Established methods are mostly either based on the Weehler-Cap-Method and limited to small antenna, or require a full 3D scan around he antenna under test. We present an alternative method for the measurement of antenna efficiency in the reverberation chamber. The measurement is based on an emission measurement method presented in [1]. Using this method, antenna efficiencies can be estimated along with the emission measurement of the equipment under test (EUT). This can help to reduce the uncertainty during radiated emission testing in the reverberation chamber. Of course, the method can also be used without an EUT present in the chamber to characterize the antenna only.

Modified TEM horn antenna for wideband applications

Abstract: This paper presents a novel method to enhance the pattern characteristics of the TEM horn antenna for 2−19 GHz frequency band. The conventional TEM horn antenna introduces some fluctuations in the main lobe radiation pattern over the center frequencies, which are 10−15 GHz. This motivated us to propose a new method to remove the aforementioned impact by carving an arc shape to the open end of exponentially tapered plates. The associated curvature of this arc is optimized to completely remove the aforementioned fluctuation. The simulation results show that the improved TEM horn antenna structure exhibits low VSWR as well as good radiation pattern over 2−19 GHz frequency band.

Flexible Hilbert-Curve Loop Antenna Having a Triple-Band and Omnidirectional Pattern for WLAN/WiMAX Applications

Abstract: A triple-band flexible loop antenna is proposed for WLAN/WiMAX applications in this paper. The proposed antenna is formed by the third-order Hilbert-curve and bending type structure which provides flexible characteristics. Even though the radius of the curvature for bending antennas is changed, a triple-band feature still remains in the proposed antenna. Moreover, the antenna exhibits the characteristics of omnidirectional radiation pattern and circular polarization. To verify the receiving performance of antenna, a simulation on the antenna factor was conducted by an EM simulator. Based on these results, the suggested antenna makes a noteworthy performance over typical loop antennas.

Oil Well Monitoring by Ultra-wideband Ground Penetrating Synthetic Aperture Radar

Abstract: Radar has been used for remote sensing and surveillance for decades Nowadays radar remote sensing and radar surveillance is used for many different things in the modern society Radar can sense objects or environments from very long distance Electromagnetic radar waves can work where and when light cannot This unique ability of radar made remote sensing techniques available in research and in industrial applications Radar can operate in any climate and any time of the day Using ultra-wideband (UWB) pulses for radar in combination with synthesizing apertures, which is so called synthetic aperture radar (SAR), enables radar to produce high resolution images in both range and azimuth directions The work presented in this thesis uses SAR for oil well monitoring SAR is seen as a good candidate to follow oil well changes in time by means of maintenance Other methods to perform this task have been introduced and implemented but they are not able to produce high resolution images from the oil well Using SAR for oil well monitoring provides high resolution images of oil well walls in order to detect the asphaltene or bitumen The resolutions of images can be enhanced by using UWB signal and SAR processing Asphaltene and bitumen are the heavy components of crude oil and capable of blocking the porous media in oil well The porous media is called damaged material when its holes are blocked by asphaltene or bitumen as it cannot pass the oil any more A decrease in oil production is the consequence of this phenomenon If these materials can be detected at very beginning stages of formation, addition of solvent at the location of the detected materials can be very helpful for oil well maintenance This thesis is divided in to two parts The first part focuses on SAR processing whereas the second one aims at antenna design and fabrication to work in a ground penetrating synthetic aperture radar (GPSAR) system In the first part, an oil well model based on the measured electrical properties of common oil well materials is introduced SAR processing is then applied to the oil well model to reconstruct SAR image of the oil well The resulting SAR image is shown to provide high resolutions so that different materials can be distinguished In the second part, a modified TEM horn antenna for SAR is designed, simulated and fabricated The antenna is customized to work in oil media A new profile model for the TEM horn antenna is proposed that modifies the antenna radiation pattern in the design The antenna measurements are shown to be in agreement with the simulated results