Modified meander line monopole antenna for broadband operation

A modified meander line monopole antenna is presented for broadband operation. The impedance and radiation characteristics of the antenna are investigated. The proposed antenna achieved a bandwidth of approximately 845 MHz with S₁₁< -10 dB, which covered the GPS, DCS, PCS, UMTS and WiBro bands. The electrical characteristics of the proposed antenna appear to be attractive for mobile terminals and repeater applications.     

一种新型VHF/UHF双频宽带车载全向天线

提出了一种工作在VHF/UHF频段的双频段宽带垂直极化车载鞭状天线。天线在VHF中馈车载鞭状天线的下辐射体顶端加一个UHF频段8λ40 MHz/4同轴扼流套,将上辐射体分为三段并在段间串接两个λ840 MHz/2倒相线圈,在天线底部加同轴扼流圈,完成了一种VHF中馈鞭状天线与一副UHF三元串联馈电直线阵天线复合的新型VHF/UHF双频段超宽频带垂直极化车载全向天线。该天线在VHF频段(30 MHz~225 MHz),UHF频段(800 MHz~880 MHz)内均具有良好的辐射特性。增益在VHF频段为1.5~4.5 dB i,在UHF频段大于6 dB i。     

Quarter-Wavelength Printed Loop Antenna With an Internal Printed Matching Circuit for GSM/ DCS/PCS/UMTS Operation in the Mobile Phone

A small-size printed loop antenna with an internal printed matching circuit capable of GSM/DCS/PCS/UMTS operation in the mobile phone is proposed. The antenna comprises an 85-mm long folded loop strip and an internal printed matching circuit encircled therein and formed by a coupling strip and an inductive strip. The loop strip is excited by the coupling strip to generate a 0.25 lambda resonant mode at about 900 MHz for GSM operation. For the inductive strip, it effectively causes a wideband higher order mode at about 1900 MHz for DCS/PCS/UMTS operation. Further, the antenna shows a uniplanar structure and requires a very small printed area of 170 mm² on the system circuit board of the mobile phone, making it easy to fabricate at low cost. Details of the proposed antenna and its radiation performances including the SAR (specific absorption rate) results are studied.     

A dual-L antenna with a novel tuning technique for dual frequencyapplications

A planar dual-L antenna with a novel tuning technique is presented for an integrated GPS/PCS dual-band application. The tuning structure is made of a metal stub attached to one of the shorting plates of the dual-L, antenna, and thus facilitates the independent tuning for lower frequency bands. Simulation and measurements were performed and dual bands of 1565.19 MHz-1585.65 MHz and 1850 MHz-1990 MHz with a return loss better than -10 dB were achieved     

车载鲨鱼鳍式超宽带多功能天线的研制

设计了一种用于车载应用的新型超宽带鲨鱼鳍天线。该天线工作频域覆盖了应用于车载通信的四个宽频带(824~960 MHz、 1 710~ 2 170 MHz、 2 300~ 2 690 MHz 以及3 300~ 5 000 MHz ),使得该天线系统集卫星导航、移动通信、WiFi、蓝牙、FM收音等多功能性于一体。主集天线尺寸为50 mm ×42 mm ×1.6 mm ,且由1/4椭圆单极子枝节和矩形单极子枝节组成,并将天线垂直放置在鲨鱼鳍式金属板上,从而方便了天线的制作和加工。仿真结果表明,全频段驻波比小于4 dB,全频段天线隔离度小于-15 dB ,且包络相关系数(Envelope Correlation Coefficient,ECC)小于0.1。与最大增益和辐射效率方面的实测值相比,该天线的模拟结果显示出良好的一致性,可广泛应用于车载通信系统中。     

A narrow-frame antenna for WWAN/LTE/WiMAX/WLAN mobile phones

In this paper, we present a novel narrow-frame antenna with a size of 75 × 8 × 5.8 mm³ for 5.7 in. mobile phones. The antenna mainly consists of a monopole with four branches that are coupled to a two-branch grounded strip. Our antenna is able to cover more bands than other narrow-frame antennas by excitation of several resonant modes. The improved range of the antenna covers the following eleven bands: LTE700, GSM850, GSM900, DCS, PCS, UMTS, LTE2300, LTE2500, LTE3400 (3400–3800 MHz)/WiMAX3.5 GHz (3400–3650 MHz), WLAN5.2 GHz (5150–5350 MHz) and WLAN5.8 GHz (5725–5875 MHz). Another advantage of the proposed antenna is that it does not need any lumped element to match the antenna. The working principles of the proposed antenna are thoroughly studied. A prototype of the proposed antenna is fabricated and measured, with the results in good agreement with the simulation results.     

Design of a vehicular antenna for GPS/Iridium using a geneticalgorithm

In this paper, we describe a vehicular wire antenna, designed using a genetic algorithm that may be used for both the GPS and Iridium systems. It has right-hand circular polarization, near hemispherical coverage, and operates over the frequency band from 1225 to 1625 MHz. This antenna was simulated using the numerical electromagnetics code (NEC) and then fabricated and tested. The antenna consists of five copper tubing segments connected in series, has an unusually odd shape, and is very inexpensive. It fits in a volume approximately 10 cm×10 cm×15 cm, The input voltage standing wave ratio (VSWR) and circular polarization radiation patterns were computed and measured. The VSWR was under 2.2 at the design frequencies of 1225, 1575, and 1625 MHz. The gain varied by less than 12 dB for a 170° sector; it generally fell off near the horizon so the variation was less for 150° and 160° sectors. This new design process, which uses a genetic algorithm in conjunction with an electromagnetics code, produces configurations that are unique and seem to outperform more conventional designs     

Triple-frequency planar monopole antenna for side-feed communication device on GSM/DCS/PCS operation

A novel side-feed planar monopole antenna capable of triple-frequency operation at about 900, 1800 and 1900 MHz is presented. The planar monopole antenna occupies a small area of 6/spl times/31 mm, and is easily made using thin copper. The planar monopole antenna can be side-fed and mounted perpendicularly to the main circuit board of a communication device so that it offers a novel design with a free degree of feed point so as to save device space, resulting in a low profile to the system ground plane. In addition, the obtained impedance bandwidths of the proposed antenna at about 900, 1800 and 1900 MHz can cover the GSM (890-960 MHz), DCS (1710-1880 MHz) and PCS (1850-1990 MHz) bands.     

CPW-fed wideband planar monopole antenna for operations in DCS, PCS, 3G, and Bluetooth bands

A novel CPW-fed wideband planar monopole antenna with a symmetrically slope ground plane is proposed. By choosing the suitable slope angle of this symmetrically slope ground plane, wideband operation can be obtained. From the experimental results, the operating mode has an impedance bandwidth of about 1162 MHz (1700-2862 MHz) that covers the DCS band (1710-1880 MHz), PCS band (1850-1990 MHz), 3G band (1920-2170 MHz), and Bluetooth band (2400-2483 MHz). The proposed antenna within these operating bands has similar monopole-like radiation patterns. It is suitable for application to wireless communication systems with its relatively low profile.     

Wide tunable dual-band reconfigurable antenna

Presented is an antenna that allows independent and versatile dual frequency and bandwidth reconfiguration by using simple external matching circuits. Simulations suggest that the antenna has a total tuning range of 2118 MHz (from 778 to 2896 MHz) while maintaining a return loss above 6 dB. In addition, the antenna is capable of operating as a penta-band cellular phone antenna. This kind of antenna is typically required to work within the GSM900, GPS1575, GSM1800, PCS1900 and UMTS2100 bands.     

Very low profile mobile phone antenna

A very low profile antenna with a simple structure and operation, for use inside a handheld mobile phone, is presented. The antenna achieves a triple-band response, covering the E-GSM (880-960 MHz), DCS (1710-1880 MHz) and PCS (1850-1990 MHz) bands for a voltage standing wave ratio less than 3 and a total radiation efficiency of more than 50%, in all bands. Because of its novel design and structure it occupies only 1.15 cm/sup 3/ of volume. Computed and measured results are presented and compared     

Application of adaptive array antenna to a TDMA cellular/PCS system

This article discusses the use of an adaptive array antenna technology in a TDMA cellular/personal communications services (PCS) system and demonstrates that the adaptive array antenna improves cell coverage, provides better signal quality, and reduces cost of deployment of cellular/PCS service in a given area     

Optimization of PIFA-IFA combination in handset antenna designs

As commercial needs have expanded the functions of the wireless cellular handsets, multiantenna development in one handset has become more and more common. This paper addresses a multiantenna solution for the wireless handset application. A planar inverted "F" antenna (PIFA) was designed as the main antenna of the handset to cover the 800 MHz band (824 MHz-894 MHz) and the 1900 MHz band (1850 MHz-1990 MHz). A side-mounted inverted "F" antenna (IFA) was designed as the 1575.42 MHz global positioning system (GPS) antenna. The location of the feed/ground pins of both antennas affected not only the total antenna efficiency, but also the polarization of the GPS IFA. The length of the GPS IFA affected the isolation between the two antennas and the specific absorption rate (SAR) of the PIFA at the 1900 MHz band. A three-dimensional efficiency measurement of the prototypes in both free space and against-head position will be presented. Measurement of SAR and its distribution will also be presented to demonstrate the impact of the IFA on the near field of the PIFA.     

Compact PIFA for 2.4/5 GHz dual ISM-band applications

A compact and novel modified planar inverted-F antenna (PIFA) for dual ISM-band application is proposed. The proposed antenna, including a small ground plane, occupies a volume of 20/spl times/23.7/spl times/0.8 mm/sup 3/ (FR-4). The impedance bandwidth with 10 dB return loss is about 150 MHz (2380-2530 MHz) for 2.4 GHz band and 1450 MHz (5130-6580 MHz) for 5 GHz band. The measured radiation patterns are approximately omnidirectional and yield a gain of 1.0 dBi at 2440 MHz and 3.98 dBi at 5600 MHz, respectively.     

Dual-band CPW-fed Y-shaped monopole antenna for PCS/WLAN application

A rectangular notch is introduced to expand the impedance bandwidth of a dual-band planar monopole antenna for application in PCS/WLAN systems. The antenna is fed by a CPW line and resembles the shape of the letter 'Y'. Prototypes of the proposed antenna have been constructed and tested. Good measured radiation characteristics of monopole-like patterns, 14.4 and 34.1% bandwidths, and 3 and 4.3 dBi peak antenna gains for the lower (1.95 GHz) and upper (5.45 GHz) bands have been obtained.     

加载新型复合左右手传输线单元的宽带单极子天线设计

提出了一种新颖的一维复合左右手传输线(CRLH-TL)单元,并将其加载到传统微带馈电的单极子天线上,设计出一种宽带的变形单极子天线。该宽带天线工作在1.67~2.67GHz,相对带宽达到了46%,有效地覆盖了DCS(Digital Cellular System,1710~1880MHz)、PCS(Personal Communication Service,1850~1990MHz)、Wi-Fi(Wireless Fldelity,2400~2480MHz)等多个通信频段。首先,利用CRLH-TL的相位补偿效应,结合传统单极子天线的自身谐振,得到多个谐振工作频点;然后,通过参数优化,使得其中的两个工作频点相互靠近形成一个更宽的工作频段,并且在工作频段内获得了较好的增益和稳定的方向图。最后,对所设计的天线进行实物加工并测试,测试结果与仿真结果吻合良好。     

Hepta-Band Internal Antenna for Personal Communication Handsets

Modern personal communication handsets are shrinking in size and are required to operate at multiple frequency bands for enhanced functionality and performance. This poses an important challenge for antenna designers to build multiband antennas within the limited allowable space. In this paper, an internal antenna covering seven frequency bands is presented for personal communication handsets. The proposed antenna operates at GSM (880-960 MHz), DCS (1710-1880 MHz), PCS (1880-1990 MHz), UMTS (1900-2170 MHz), WiBro (2300-2390 MHz), Bluetooth (2.4-2.48 GHz), and WLAN (5.0-5.5 GHz) frequency bands. Measured input return loss of the antenna is better than dB at all the frequency bands with reasonable radiation performance. Antenna volume is 30 mm times15 mm times 4.0 mm (1.8 cm) that makes it attractive for modern multiband and multifunctional slim handsets.     

Empirical formula for propagation loss in land mobile radio services

An empirical formula for propagation loss is derived from Okumura's report in order to put his propagation prediction method to computational use. The propagation loss in an urban area is presented in a simple form: A + B log10R, where A and B are frequency and antenna height functions and R is the distance. The introduced formula is applicable to system designs for UHF and VHF land mobile radio services, with a small formulation error, under the following conditions: frequency range 100-1500 MHz, distance 1-20 km, base station antenna height 30-200 m, and vehicular antenna height 1-10 m.     

A flat diversity antenna by disk loaded monopole and three notches

This paper proposes a flat diversity antenna, consisting of a disk loaded monopole antenna (DLM) and three notch antennas fabricated on the same disk as a vehicular diversity antenna. This paper presents feed circuits for the notch array, and measurement results of the impedance characteristics and radiation patterns of the flat diversity antenna. To verify the diversity effect of this antenna, propagation measurements were made at 900 MHz band. As a result, the new flat diversity antenna is shown to be useful as a diversity antenna of mobile telephone systems     

Broadband compact stacked T-shaped DRA with equilateral-triangle cross sections

A compact T-shaped dielectric resonator antenna (DRA) with two equilateral-triangle cross sections is investigated in this letter. The DRA is vertically placed on a finite ground plane and excited by a coaxial probe to provide broadband and conical radiation patterns. In order to examine the proposed design, simulations and measurements were employed to investigate the proposed antenna, and a good agreement between them was obtained. The proposed design produces an impedance bandwidth of more than 60% from 1.6 to 3.1GHz, which effectively covers several promising application bands in contemporary wireless communication systems, such as digital communication systems (DCS: 1710-1880MHz), personal communication systems (PCS: 1850-1990MHz), universal mobile telecommunication systems (UMTS: 1920-2170MHz), wireless local area networks (WLANs: 2.4-2.485GHz). Additionally, stable conical patterns were also obtained within the interest frequency band.