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In this paper, an RF wire-to-board connector with an ultra-low loss cable is proposed to reduce interconnection loss at mmWave frequencies. A new type of the rotary connector structure with a mating height of 1.4 mm is designed to achieve a bandwidth from DC to 45 GHz. This rotary type RF wire-to-board connector may provide ultra-low loss connection solutions for 5G mobile and base station devices, radar systems, satellite modules, etc. Also, a DSFP high speed connector design is presented, where each of the dual high-speed channels in this connector may operate up to 28 GHz. With a PAM4 modulation technique, the aggregated data rate of the DSFP may reach 224 Gbps to support high-speed transmissions for 5G applications.

This paper presents antenna designs to enhance the performance and electromagnetic susceptibility of the UHF radio frequency identification (RFID) tag on vehicles for Electronic Toll Collections (ETC). By adjusting the radiation pattern of the tag antenna upwards and selecting proper installation environments for tag durability, better performance for the ETC can be achieved. To validate those designs, RFID measurements in the field test site of Telecom Technology Center are performed. The results reveal that the proposed tag antennas may effectively improve the detection rate and read range of the RFID system for the ETC and also reduce electromagnetic interferences from nearby mobile base stations.

A low-profile RF wire-to-board connector design for 5G mobile communications and WiGig applications is presented in this paper. A new connector structure with a mating height of only 0.7mm to achieve a bandwidth from DC up to 70GHz is proposed. This RF connector design may provide jump wire connections in devices for 5G wireless communications and other millimeter wave systems.

A series-fed cavity-back patch array antenna for a miniaturized 77GHz radar module is presented in this paper. Inherently, the microstrip patch antenna has a wider bandwidth with a thicker substrate. However, a ground coplanar waveguide (GCPW) to feed the patch array antenna has less surface wave radiation loss with a thinner substrate. Therefore, a three-layer cavity-back patch array antenna is proposed to fulfil both requirements. Six 10-element series-fed arrays for the 77GHz radar module with the total dimensions of only 36(L) ×18(W)×7(T) mm3 are designed. Good radiation properties in a bandwidth from 77 to 81GHz are obtained.

A compact monopole and inverted-F antenna design for 2.4 GHz ISM band (2400–2485 MHz) and 1.575 GHz GPS operations suitable to be embedded within a wrist-worn wireless communication device is presented. Those antennas are fabricated on a polycarbonate and acrylonitrile-butadiene-styrene blend substrate with a three-dimensional etching process for irregular plastic materials. The wrist-worn device with and without a solid hand phantom model is evaluated. The radiation efficiency of the antennas can reach 80% for the ISM band and 63% for the GPS band without the hand phantom model. With the hand phantom model, the radiation efficiency reduces in half for both the ISM and GPS bands due to lossy materials in the phantom model. Good agreements between simulations and measurements are obtained. Moreover, the specific absorption rate of the device for the ISM band is measured and the results are much lower than the limit required by the FCC. This build-in antenna design can be applied in the wearable wireless communication device.

A novel structure of the near-field communication (NFC) antenna design for a tablet PC is proposed. This tablet PC has a narrow border and full metallic back-cover. A miniaturized loop antenna design is achieved by attaching ferrite sheets on both sides of the loop antenna. The ferrite sheets may reduce eddy currents induced on the adjacent metallic back-cover by the loop antenna to improve the communication range of the NFC. Only the edge of the tablet PC allows the antenna to radiate due to the full metallic back-cover. Thus, the NFC antenna needs to be narrow to be installed on the edge of the tablet PC. Therefore, we propose a miniaturized NFC antenna with the dimensions of $41.5\ ({L}) \times 7.5\ (W) \times 0.45\ (T)\ \hbox{mm}^3$ only. Simulated magnetic field distributions are consistent with measured voltage distributions. This design has a good communication range more than 6 cm in front of the touchscreen panel and reaches 2 cm over the other side above the metal back-cover.

This paper presents two near field reader antennas for applications in the UHF radio frequency identification (RFID) system. Strong vertical and horizontal magnetic fields in near zones are respectively excited by those two reader antennas, so that the readable distance of the nearfield tags attached on objects can be enhanced significantly. Thus, the reader antennas are capable of near-field identification and positioning applications, such as a casino gaming table. For the gaming management system, many stacked chips with tags embedded can be recognized by using near-field reader antennas so that manpower may be saved to significantly improve counting efficiency.

We reported the progress of developing 400-Gb/s optical transceivers with 1.3-μm electro-absorption modulators for optical interconnect applications in data centers. The key technologies include high-speed light sources, silicon photonics based WDM multiplexers/de-multiplexers, driving and receiving circuits, signal processing and monitoring schemes.

A planar antenna design is developed for integration with a temperature sensor to monitor frozen goods condition during transportation. Antenna geometries as well as radiation patterns are configured to address the distinctive propagation environment, which is the cargo space filled with stacks of thermal insulated boxes. The sensor, a Bluetooth module, periodically relays temperature data to a dedicated reader or the driver's smart phone. With these data, quality of service can be ensured for cold chain logistics. The sensor antenna, which is mounted on the surface of the insulated box, has a sideways pattern that is aimed to propagate along the gap between boxes and avoid attenuation from perishable goods within. Numerical simulations of this distinctive propagation environment are conducted to determine the required antenna polarization. To demonstrate advantages of the proposed temperature monitoring system, several field tests have been devised. Received signal strength indicators are measured for stacked containers in both closed and open truck environments to validate the superior performance of the developed sensor. Stable connections to sensors on boxes filled with frozen goods can be made successfully in delivery trucks.

This paper presents ray tracing simulations for wave propagation at millimeter-wave frequencies to be applied in future 5G wireless communications. Since attenuation and blockage of millimeter-wave propagation in urban are much more severe than those at microwave frequencies, the line-of-sight rays and non-line-of-sight reflected rays should be dominant propagation mechanisms. Field distributions will be more constrained and therefore new approaches to improve the coverages of the 5G wireless communications will be needed. The ray tracing method can be applied to evaluate those approaches for improving field coverages in the deployment of the 5G base stations.

This paper presents a method for evaluating radio frequency identification (RFID) 3D readable ranges, implemented by integrating a spherical scanning antenna measurement system for RFID static tests in an anechoic chamber environment. Also presented with demonstrative examples are measurement efficiency in terms of total elapsed measurement time, figures of merit on characterizing the tag readable range of the static test results, and the associated system validations.

This paper presents a pattern reconfigurable antenna operating in the 36∼40 GHz band. It is projected to be used on handheld devices for future 5G wireless communications. The proposed design is a multi-antenna system, which comprises a reconfigurable power divider that excites one or multiple antennas according to system's commands. The diversified antenna excitation combinations provide various radiation patterns to meet the wideband mobile communication need of the future 5G handset. The main challenge is to maintain a proper matching condition under different excitation configurations. In the proposed design, a simple matching circuit is employed to match all cases. A total of fifteen radiation patterns is provided with a four-antenna system.

In this paper, a compact planar monopole antenna with eight-band LTE/WWAN (LTE700/2300/2500/GSM850/900/1800/ 1900/UMTS) operation for laptop computer application is presented. This design structure comprises a bent driven strip and two coupled strips, which can contribute multiple resonance modes to combine two wide operating frequency bands covering 665–1023 MHz and 1612– 2924MHz. The proposed antenna fed by a 50-Ω coaxial cable occupies a small size of only 65(L)× 11(W)× 0.4(H)mm3, so it can be flexibly embedded inside the casing of the laptop computer as an internal antenna. A fabricated prototype of the antenna is tested and analyzed. Experimental results exhibit that nearly omnidirectional coverage and stable gain variation across the desirable LTE/WWAN bands can be obtained with the antenna.

A novel miniature multibranch inverted-F antenna (IFA) suitable for penta-band Wireless Wide Area Network (WWAN) applications is presented. The antenna is fabricated on a direct bond copper substrate and consists of multibranch strips, which occupies a very small size of 83(L)× 7(W) × 0.5(H) mm3 to be easily embedded inside the laptop computer as an internal antenna. By properly designing the antenna operated as an inverted-F antenna, two frequency bands covering 813–993 and 1703–2196 MHz for the GSM850/900 and DCS/PCS/UMTS operations are achieved with good radiation efficiencies. Compared with other studies, the proposed antenna with a compact size is suitable to be installed in the laptop computer for the WWAN applications. © 2011 Wiley Periodicals, Inc. Microwave Opt Technol Lett 53:547–550, 2011; View this article online at wileyonlinelibrary.com. DOI 10.1002/mop.25802

A compact antenna capable of generating two wide operating bands to cover the GSM850/900 (824-960MHz) and GSM1800/1900/UMTS (1710-2170MHz) systems is presented. The antenna occupies just 81.5(L)×7(W)×0.5(H)mm3 on the top edge of the supporting metal frame of the display panel, and is therefore easily embedded in the ultra-thin laptop computers as an internal antenna. The antenna is implemented using a ceramic substrate and consists of multi-branch strips. Based on the principle of the inverted-F antenna, our design yields two operating bands covering 816-983MHz and 1703-2196MHz can be achieved with good radiation performance for our design. The proposed antenna is thus suitable to be installed in the ultra-thin laptop computers for Wireless Wide Area Network applications.

In this letter, a novel compact inverted-F antenna with dual-band property for WLAN applications is presented. It comes with a C-shaped radiator and two meander shorting strips, which only occupy a small size of 35 (L)3 (W) mm to be easily embedded inside a laptop computer as an internal antenna. This design can radiate with two operating bands covering 2.38-2.54 and 4.99-5.96 GHz. By properly forming these two shorting strips, the effects due to the antenna near the external casing can be suitably tackled for actual application. Nearly omnidirectional coverage to enhance the communication quality can be obtained with our design. Therefore, the proposed antenna with a compact size is well suitable for WLAN operation in a laptop computer.

In this letter, a compact edge-shorted slot microstrip antenna with good near-field performance for radio frequency identification (RFID) applications is proposed. It is composed of a rectangular slot radiator, a shorting wall, and a pair of shorting strips, which occupy a small size of 40 (L)×16 (W)×6 (H) mm3 to be easily embedded inside a handheld reader device as an internal antenna. By properly designing a thin slot and a shorting wall, strong and uniform electric field distribution surrounding the near-zone region can be obtained with the antenna. This design can not only achieve an operating band of 2.38-2.55 GHz, but also generate large capacitive coupling effect to significantly enhance the near-field performance for actual application. Experiments exhibit that the proposed patch antenna may well function as a handheld reader antenna to detect the dipole-like tags through capacitive coupling for RFID near-field operation.

Recent developments in the field of radio frequency technologies have led to numerous challenges in providing comprehensive performance for the next generation wireless networks. Meanwhile RFID as the one of important core technology in toward this future approach, have been implemented extensively for different kind applications. Those applications direct to the obviousness that issues in electromagnetic, signal collusion, privacy and security have decreased RFID role in industry implementation. In designing RFID devicesmore challenges and difficulties are become significant due to the low-cost and low-source factors. This has encouraged researchers to think hard in developing more secure and accurate RFID tags. Therefore this edition present the papers that addressing the solution diverse issues in RFID system such as: tag antenna and propagation, communication protocol, security and privacy, system tools, RF-based localization, RFID system architecture, deployment issue, and also applications. Chi-Yi Lin and Wen-Tsung Cheng from Tamkang University, Szu-Chi Wang from National I-Lan University implemented hybrid system integrating GPS and RFID technologies to address three important factors in providing detail and reliable end to end logistics managements. Their implementation focuses in multiple heterogeneous location system in approach to extend functionality in information delivering method.

A coplanar waveguide (CPW)-fed planar monopole antenna with triple-band operation for WiMAX and WLAN applications is presented. The antenna, which occupies a small size of 25(L) × 25(W) × 0.8(H) mm3, is simply composed of a pentagonal radiating patch with two bent slots. By carefully selecting the positions and lengths of these slots, good dual stopband rejection characteristic of the antenna can be obtained so that three operating bands covering 2.14-2.85, 3.29-4.08, and 5.02-6.09 GHz can be achieved. The measured results also demonstrate that the proposed antenna has good omnidirectional radiation patterns with appreciable gain across the operating bands and is thus suitable to be integrated within the portable devices for WiMAX/WLAN applications.

A compact planar monopole antenna with standard band-notched characteristic suitable for ultrawideband (UWB) applications is presented. This microstrip-fed antenna, consisting of a square slot patch with a vertical coupling strip, only occupies a small size of 15 (L) × 15 (W) × 1.6 (H) mm3. By properly designing the strip placed at the center of the patch, good frequency rejection performance of the antenna with a wide operating band from 3.05 to 11.15 GHz can be obtained. Compared to other designs, the antenna has a quite simple structure to make the band-notched property to reduce the effect caused by the frequency interference. Furthermore, fairly good omnidirectional radiation patterns and transmission responses both indicate that the proposed antenna is well suited to be integrated within various portable devices for UWB operation.

An inverted-F antenna with multiband operations for Long-Term Evolution (LTE700/2300/2500), wireless wide area network (WWAN), GPS, WiMAX (2.3/2.5/3.5 GHz), and WLAN (2.4 GHz) applications is presented. The antenna consists of multibranch strips and is fabricated on both sides of an Al2O3 ceramic substrate, which has a compact size of 97 (L) × 11.2 (W) × 0.5 (T) mm3 to be embedded inside the laptop computer as an internal antenna. Four operating bands covering 646-983, 1503-1589, 1696-2963, and 3396-3646 MHz for the LTE, WWAN, GPS, WiMAX (2.3/2.5/3.5 GHz) and WLAN (2.4 GHz) systems are achieved with good radiation efficiencies.

A novel miniature monopole tag antenna for passive UHF radio frequency identification (RFID) operation is presented. The antenna possesses a two-sided structure that is printed on an FR4 substrate and fed by a 50-? microstrip line. By properly using helical strips and vias, the antenna size can be reduced to a small volume of 10 (L) × 9.5 (W) × 0.8 (H) mm3 to be easily integrated within various portable devices. A miniaturized quasi-lumped circuit is also designed to achieve a good impedance matching between the antenna and the tag chip. Experimental results demonstrate that the antenna has a suitable operating band about 914-939 MHz and also nearly omnidirectional radiation patterns with proper gain. Moreover, the proposed compact tag antenna, capable of achieving a maximum readable range about 5.6 m with an effective isotropic radiated power (EIRP) equal to 4 W, is well suitable for RFID applications.

A multibranch inverted-F antenna with multiband operations for long-term evolution (LTE), pentaband wireless wide area network (WWAN) and IMT-E (2.6 GHz) applications is presented. The antenna consists of multibranch strips and is fabricated on a direct bond copper (DBC) substrate, which has a compact size of 96 (L) × 11.2 (W) × 0.5 (H) mm3 to be embedded in the laptop computer as an internal antenna. Three operating bands covering 663-993, 1689-2190, and 2449-2783 MHz for the LTE, GSM850/900 and DCS/PCS/UMTS, and IMT-E systems are achieved with good radiation efficiencies. The proposed antenna can be embedded in the laptop computer for the LTE, WWAN, and IMT-E applications.

A miniaturized quadrature hybrid coupler, a rat-race coupler, and a 4 times 4 Butler matrix based on a newly proposed planar artificial transmission line are presented in this paper for application in ultra-high-frequency (UHF) radio-frequency identification (RFID) systems. This planar artificial transmission line is composed of microstrip quasi-lumped elements and their discontinuities and is capable of synthesizing microstrip lines with various characteristic impedances and electrical lengths. At the center frequency of the UHF RFID system, the occupied sizes of the proposed quadrature hybrid and rat-race couplers are merely 27% and 9% of those of the conventional designs. The miniaturized couplers demonstrate well-behaved wideband responses with no spurious harmonics up to two octaves. The measured results reveal excellent agreement with the simulations. Additionally, a 4 times 4 Butler matrix, which may occupy a large amount of circuit area in conventional designs, has been successfully miniaturized with the help of the proposed artificial transmission line. The circuit size of the Butler matrix is merely 21% of that of a conventional design. The experimental results show that the proposed Butler matrix features good phase control, nearly equal power splitting, and compact size and is therefore applicable to the reader modules in various RFID systems.

DGEBA type epoxy resin, D.E.R. 331, was mixed with barium titanate, Y5V fillers, then cured with diaminodiphenyl methane (DDM). It was found that the dielectric constant at high frequency, 1 M–1 GHz, increases with the solid content of barium titanate. By adding 80 wt.% of Y5V fillers, the dielectric constant at 1 GHz can be increased from 3.2 of the sample without fillers to 13.1. A Lichtenecker's mixing model was proposed to describe the dielectric constant profile dependent on the filler loading. Furthermore, a model chip antenna was prepared and covered by an epoxy–barium titanate composite. The fundamental resonant mode of the antenna is excited at 2.452 GHz with a 10-dB return-loss bandwidth of about 191 MHz. It suggests that the antenna would be applied in 2.4 GHz ISM band for wireless communications.

The popularity of Radio Frequency IDentification (RFID) in realistic applications has produced a variety of interference problems. Typical ones are the existences of metal structures in the neighborhood of reader or tag antennas, which cause strong electromagnetic (EM) scattering fields. To overcome these types of interferences, an antenna subsystem is proposed and developed for the RFID reader antenna applications at 2.45GHz in the near-zone tag detection. The term “near-zone” indicates that the application region can be relatively arbitrary and can be close to the aperture of a phased array antenna. The potential applications can be illustrated by the scenario of indoor product transportation system in the department stores, where the I/O management system is performed at a designated spot (or the detection zone). In this case, the tags on the commercial products will move on the transportation belt through a detection zone.

A combination of the Near Field Communication (NFC) antenna and wireless charging coil for a mobile device is proposed in this paper. By integrating the single dual-mode antenna, the mobile device can provide both the NFC and wireless charging functions. The NFC multi-loop antenna transmits power in a near range by using magnetic field coupling. A capacitive matching circuit is added to achieve good coupling with a nearby NFC device at 13.56 MHz. On the other hand, the wireless charging system harvests energy in also a near range with magnetic field coupling at 100 kHz. A PCB coplanar design is employed to integrate our design into the mobile device. Simulated and measured results are presented and good performance for both NFC and wireless charging is achieved.

In this paper, electromagnetic interferences (EMI) occurred in electric power and telephone lines due to radiation at a frequency of 525 kHz from an aeronautical radio navigation station are presented. The induced voltages measured on those lines caused malfunction or even damage to some electrical devices inside the station. To understand those EMI effects further, an FDTD software package, XFDTD, was applied to evaluate the induced voltages. It was found that the major reasons resulting in interferences were due to longitudinally induced voltages and ground potential rises. They were caused by the radiation from the antenna of the station and current flowing through the ground grids, respectively. In addition, mitigation of EMI was performed to correct those problems by applying separate grounding systems, shielding the telephone, and using underground cables instead of overhead lines near the station. Currently, the whole system, including electric power, navigation and telephone, inside the station operates normally

This paper presents a ray method for determining wave propagation over hilly terrain. Terrain profiles between the transmitting and receiving antennas are obtained from digital maps, and a profile linearization method is developed to simplify those terrain profiles into 2‐D wedges and trapezoids. A heuristic uniform theory of diffraction (UTD) solution including multiple‐edge transition zone diffractions is then applied to determine path losses for waves propagating through those 2‐D structures. All forward diffracting contributions, plus a ground reflection near the receiving antenna, are included to evaluate the field distributions. Measurements of VHF TV signals in northern Taiwan have been performed to compare with the UTD simulations. Good agreements are obtained, considering the complexity of wave propagation through irregular terrain.

This paper presents a novel reconfigurable antenna to be embedded in a handheld device operating in the VHF band from 136 to 174MHz. This device can be applied for an emergency wireless communication system during natural disasters. A reconfigurable structure is included to switch the embedded antenna having a narrow bandwidth to cover the required VHF band with an acceptable radiation efficiency.

In this paper, a low-profile dipole RFID tag antenna with a lateral omni-directional pattern is presented. The proposed low-profile antenna can be easily integrated into a size-limited RFID module. To achieve the lateral omni-directional pattern, two shorting pins are added in this antenna structure, which performs better in stacking environments. Therefore, the proposed antenna is suitable for cold-chain logistics applications.

A novel miniature monopole tag antenna for passive Ultra-High Frequency (UHF) radio frequency identification (RFID) operation is presented.The antenna possesses a two-sided structure that is printed on an FR4 substrate and fed by a 50-Ω microstrip line. By properly using helical strips and vias, the antenna size can be reduced to a small volume of 10 (L) × 9.5 (W) × 0.8 (H) mm3 to be easily integrated within various portable devices. A miniaturized quasi-lumped circuit is also designed to attain a good impedance matching between the antenna and the chip. Experimental results demonstrate that the antenna has a suitable operating band about 914–939 MHz and also quite omnidirectional radiation pattern with appreciable gain. Moreover, the proposed compact tag antenna, capable of achieving a maximum readable range of about 5.6 m with an EIRP equal to 4 W, is well suited for RFID applications. © 2010 Wiley Periodicals, Inc. Microwave Opt Technol Lett 52:2770–2772, 2010; View this article online at wileyonlinelibrary.com. DOI 10.1002/mop.25596

A ray-tracing method for waves inside buildings is presented. Ray tubes are used to model the wave propagation and penetration and all the significantly reflected and transmitted ray tubes from interfaces are included. Also, the cross sections of the ray tubes at the field points are evaluated to find the spreading factors of the waves and then the geometrical optics (GO) contributions at the locations of the receiving antenna. A program has been developed according to this ray-tracing technique that can be applied to simulate waves transmitted through and reflected from electrically large complex 2D and 3D bodies. To verify this ray-tracing program, 2D moment method (MM) solutions for wave propagating in a two-room structure and also through a stair-shaped wall above a lossy ground are used to compare with those obtained from the ray tracing. Besides, comparisons of field measurements and ray-tracing simulations at 900 and 1800 MHz performed in a corridor on different floors and inside a staircase are shown. The effective complex dielectric constants of the buildings determined from a free-space method are employed in the simulations and a vector network analyzer is used for the field measurements. Good agreements are obtained. In addition, measured results for waves penetrating an exterior wall with metal-framed windows at 1290 MHz are employed to test the ray-tracing solutions, which indicate that scattering from the metal frames may be significant for field points near the windows. This ray-tracing program can be applied to evaluate the channel characteristics for the indoor wireless communications.

Due to the growing demand for business-to-customer delivery on perishable goods, a novel business model has been devised to send temperature sensitive goods to the general public without refrigerated trucks. Packages are placed in thermal insulated containers instead, while the temperature is constantly monitored by wireless sensors. Because the cargo space is full of lossy materials, the sensor-integrated antenna is designed to provide radiations in a waveguide-like propagation environment. A low-profile dipole antenna configuration is adopted. Simulation and measurement results demonstrate the proposed conformal antenna can provide the required radiation patterns with decent gains and efficiencies.

A novel low-profile inverted-F film antenna design for in-car DAB Band III (170-240 MHz) applications is presented. This antenna is attached on the front windshield of the car along the edge of the A-pillar, which occupies an area of only 238(L)×27(W)mm2 to reduce sight blockages. Good antenna performance has been obtained.

This summary paper presents a method for evaluating radio frequency identification (RFID) readable ranges, implemented by integrating a spherical scanning antenna measurement system for RFID static tests in an anechoic chamber environment. RFID tags with either forward or reverse links dominated can be evaluated in the 2D and 3D measurement modes of the static test system.

A moment method (MM) solution for analyzing the electromagnetic shielding and scattering properties of two-dimensional (2-D) objects over a lossy half space is presented. The materials of the objects can be metal, dielectric, or magnetic. Also, the lossy half space is included to simulate the effects of the earth ground or any flat homogeneous lossy surface. An MM based on a volume formulation and a special Green's function in the spectral domain is developed. Both TM/sub z/ and TE/sub z/ waves incident upon 2-D metal or lossy material structures are demonstrated for the shielding effects of those bodies in the presence of the lossy ground. Besides, the echo widths of a composite object either in free space or above the lossy half space are determined by using the MM. Some of the results are compared with those by other methods, and good agreements are obtained. The MM solution can be used to study the shielding and scattering problems for cylindrical structures located over a lossy ground.

This summary presents an integration of a shielded anechoic chamber environment for the spherical near-field antenna measurement purpose on developing the RFID static test system and provides critical characterization features for evaluating the RFID tag 3D operation performance requirements. The prototype system architecture for the static test system provides the methodology for measuring figures of merit of the tag readable range. This system is capable of performing realistic case measurements for detailed analysis requirements and to provide critical indicators based on the results for optimal RFID tag operation performance over full 3D circumference. The proposed 3D RFID static test system may be applied as an effective tool for optimal tag and reader operation performance developments.

A novel miniature inverted-F antenna for 2.4/5GHz dual-band WLAN applications in a tablet computer is presented. This antenna is composed of three radiating strips and a shorting strip, which occupies an area of 13(L)×6(W)mm2 to be mounted along the side edge of the panel. Good performance for the WLAN applications has been obtained.

A compact inverted-F antenna with multiband operations for LTE, WWAN, WiMAX and WLAN applications is presented. The antenna consists of multi-branch strips and is fabricated on both sides of the ceramic substrate, which has a compact size of 90(L)×10(W)×0.5(T) mm3 to be embedded inside an ultra-thin laptop computer as an internal antenna. Three operating bands covering 673–993 MHz, 1673–3153 MHz and 3316–3603 MHz for the LTE700/2300/2500, WWAN, WiMAX (2.3/2.5/3.5 GHz) and WLAN (2.4 GHz) systems are achieved with good radiation efficiencies.

In this paper, a planar circular patch array antenna that features electric fields focused in the near-field zone for 2.4 GHz radio frequency identification (RFID) applications is presented. This array antenna is implemented by using six circular patch elements and a microstrip feeding network with a proper input phase for each element. The array antenna is capable of enhancing electric field distributions in the near zone to charge and interrogate dipole-like passive tags near the array antenna by capacitive coupling. Readable range is measured for up to 12 tags lined up closely with 1 cm spacing. Applications using the proposed array antenna with an RFID reader by Sunlit are discussed.

Digital television (DTV) broadcasting has drawn worldwide attention in recent years. Many nations will transfer their television broadcast system from analog to digital in the coming future. The frequencies used for DTV broadcasting range from 470 to 860 MHz, a bandwidth of almost an octave. The actual frequency band allocated, however, varies from one nation to the other due to various practical considerations. The USB DTV tuner, inherently a compact and portable receiver, could be the most convenient and cost effective way to receive DTV signals on a notebook or any other multimedia device. While the circuit components and their functionalities could be integrated into a single chip on the printed circuit board, the antenna, whose length is proportional to the wavelength of the operating band, is still large in size and becomes the major bottleneck in developing compact and versatile receivers. Recently, novel antenna designs have been proposed and investigated for DTV applications in literatures [1]-[3]. While the planar monopole in [1] is large in size, the internal antenna in [2], though compact in size, is prone to damage and cannot be used in mass production. The meander line antenna in [3] is inherently a narrowband design which needs a varactor to adjust its operating frequencies upon applications. To further improve the integration capability of DTV antennas, in this paper we report a novel built-in antenna which can be completely embedded in a USB DTV tuner. The antenna geometry, design methodology, and experimental results will be introduced in the following sections.