CPW-fed compact monopole antenna for dual-band WLAN applications

A compact CPW-fed monopole antenna is proposed for dual-band wireless local area network (WLAN) operations. The proposed antenna, which consists of two strips, has compact size of 20/spl times/15.5/spl times/1.6 mm/sup 3/ including the ground. The proposed antenna effectively covers both 2.4 GHz (2.4-2.484 GHz) and 5 GHz (5.15-5.825 GHz) bands. The measured peak gains are 1.3 dBi at 2.44 GHz and 2.8 dBi at 5.32 GHz.     

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.     

Compact wideband antenna for 2.4 GHz WLAN applications

A novel compact wideband antenna for wireless local area network (WLAN) applications in the 2.4 GHz band is presented. The proposed low profile antenna of dimensions 15/spl times/14.5/spl times/1.6 mm offers 18.6% bandwidth and an average gain of /spl sim/5 dBi. The antenna can be excited directly using a 50 /spl Omega/ coaxial probe.     

Compact planar multiband antenna for GPS, DCS, 2.4/5.8 GHz WLAN applications

A compact single-feed multiband planar antenna configuration suitable for GPS, DCS, 2.4/5.8 GHz WLAN applications is presented. The antenna has dimensions 38/spl times/3/spl times/1.6 mm and offers good radiation and reflection characteristics in the above frequency bands. The antenna has a simple geometry and can be easily fed using a 50 /spl Omega/ coaxial probe.     

Printed compact dual band antenna for 2.4 and 5 GHz ISM band applications

A printed compact dipole antenna for dual ISM band (2.44 and 5 GHz) is presented. The proposed antenna fed by using a 50 /spl Omega/ coaxial line occupies a volume of 15/spl times/40/spl times/1 mm/sup 3/ (FR-4, permittivity 4.6). The impedance bandwidth for 10 dB return loss is about 400 MHz (from 2170 to 2570 MHz) at 2.4 GHz band and over 2300 MHz (from 4690 to beyond 7000 MHz) at 5 GHz band. The measured radiation gains range from 1.20 to 1.41 dBi at 2.4 GHz band and from 2.25 to 3.44 dBi at 5 GHz band, respectively.     

CPW-fed circular slot antenna with slit back-patch for 2.4/5 GHz dual-band operation

A circular slot antenna fed by a coplanar waveguide (CPW) is proposed for dual-band operations. Dual frequency bands that cover the 2.4 GHz (2400-2484 MHz) and 5 GHz (5150-5825 MHz) bands were obtained by embedding a pair of slits in the circular back-patch that is printed on the backside of the substrate and concentric with the circular slot. This design resulted in broadside far-field patterns with low cross-polarisation levels in both frequency bands and a small antenna size of 40/spl times/40 mm with the ground plane regarded as part of the antenna structure.     

Design of dual-band slot antenna with double T-match stubs

A simple and compact design of dual-band slot antenna is presented. Fed by a CPW, the antenna is printed on a single-layer PCB with extremely low manufacturing cost. A pair of T-match stubs is employed to generate the dual resonances in the 2.4-2.5 and 5-6 GHz bands. The antenna of small radiating area 11/spl times/28 mm/sup 2/ is demonstrated on an FR4 PCB with ground plane size of 31/spl times/35 mm/sup 2/. Robust radiation performances are achieved, including in-band gain flatness within +/- 0.5 dB and polarisation isolation better than 15 dB. Consistent radiation patterns for both bands are obtained with peak gains about 3 and 4 dBi in the lower and upper bands, respectively.     

Development and analysis of a folded shorted-patch antenna with reduced size

The length of a wall-shorted rectangular patch antenna can be reduced from /spl sim//spl lambda//sub 0//4 to /spl sim//spl lambda//sub 0//8 by a simple folding operation, which results in a stacked shorted-patch (S-P) structure with a resonant frequency that can be controlled by modifying the distance between the stacked (lower and upper) shorted-patches. A theoretical analysis based on a simple transmission-line model is presented and compared with numerical simulations, showing good agreement if the height of the folded patch is much smaller than the patch length. The physical insight of the variation of the resonant frequency for this reduced-size antenna can be understood by considering the antenna as a shorted patch loaded with a capacitor. An experimental verification is carried out for a 15 mm/spl times/15 mm/spl times/6 mm folded S-P antenna prototype designed for the 2.4 GHz ISM band that can achieve a 10-dB return loss bandwidth of 4% and results in a nearly omni-directional radiation pattern.     

Compact ultra-wideband printed antenna with band-rejection characteristic

A novel and compact ultra-wideband printed antenna with band-rejection characteristic is proposed. By cutting an L-shaped notch on the radiating patch, the impedance bandwidth of the proposed antenna can be enhanced. In addition, a C-shaped slot is introduced to obtain the band-rejection operation of the antenna. The antenna, with compact size of 15.5/spl times/21 mm including the ground plane, operates over 3.08-10.97 GHz and has the rejected band from 5.03 to 5.91 GHz.     

Multi-band monopole antenna with inverted U-shaped parasitic plane

A microstrip-fed printed monopole antenna having a parasitic plane is proposed for multi-band applications. By inserting an inverted U-shaped parasitic plane on the bottom of the dielectric substrate, the proposed antenna can easily cover DCS/UMTS/WiBro/2.4 GHz WLAN and 5.2/5.8 GHz WLAN bands at the same time. In addition, a /spl Gamma/-shaped slit is inserted on the main patch to cover the GSM frequency band. Experimental and numerical results of the designed monopole antenna are presented and analysed.     

Compact CPW-fed monopole antenna for 5 GHz wireless application

A compact and simple coplanar waveguide (CPW)-fed monopole antenna for 5 GHz wireless communication is proposed. By properly adjusting the lengths of both the monopole strip and the inverted L-shaped ground, the designed antenna, with, including ground plane, only 9/spl times/9.5 mm/sup 2/, can operate at the desired 5.2 or 5.8 GHz band. The electromagnetic coupling effect between the radiating strip and the ground on excitation of the resonant mode has been studied. Prototypes of the proposed antenna have been constructed and experimentally studied. Measured results show a -10 dB impedance bandwidth and an average antenna gain of 400 MHz and >6 dBi, respectively.     

Feed for dual-band printed dipole antenna

A dual-band printed dipole antenna is proposed for WLAN applications in the 2.4 and 5.2 GHz bands. A spur line was etched on the arms of the printed dipole to achieve the dual-band operation. The printed dipole antenna with a simplified matching network is proposed. The novel simplified feed structure consists of a pair of parallel metal strips printed on the opposite sides of the dielectric substrate and connected to a 50 /spl Omega/ microstrip line with a truncated ground plane. This feeding network does not require additional transition devices, such as a T-junction, power divider, tuning stub or microstrip-to-coplanar stripline balun.     

Wideband stubby monopole antenna for mobile phone

A novel stubby monopole antenna fabricated using a single metal plate is presented. A prototype of the proposed antenna with a cross-sectional area of 10/spl times/10 mm and a length of 20 mm is implemented, and the antenna shows a wide operating bandwidth of about 10.9 GHz, making it easy to cover the UMTS band and the 2.4/5.2/5.8 GHz WLAN bands for mobile/WLAN dual-mode operation of a mobile phone.     

Dual-band twin stepped-patch monopole antenna for WLAN application

By using twin stepped-patch radiators and a protruded ground, a micro-strip-fed monopole antenna with wide dual-band operation can be obtained. The proposed antenna with an overall size of 32 times 25 mm can excite resonances at the 2.61 and 5.52 GHz bands with impedance bandwidths of 710 MHz (2.32-3.03 GHz) and 1.56 GHz (4.77-6.33 GHz), average antenna gains of 2.9 and 3.5 dBi, respectively, and also monopole-like radiation patterns. These properties make the antenna suitable for 2.4/5.2/5.8 GHz WLAN applications.     

A miniature UWB planar monopole antenna with 5-GHz band-rejection filter and the time-domain characteristics

A planar monopole antenna with a staircase shape and small volume (25/spl times/26/spl times/1 mm/sup 3/) is proposed in this paper. With the use of a half-bowtie radiating element, the staircase-shape, and a modified ground plane structure, the proposed antenna has a very wide impedance bandwidth measured at about 11.6 GHz (2.9-14.5 GHz, bandwidth ratio about 1:5) below VSWR 2 including the WLAN band notched in the vicinity of 5 GHz. An omnidirectional radiation pattern is obtained. The group delay which is an indication of linearity between two proposed antennas is less than 1 ns. The electrical characteristics in terms of frequency and time domains and physical ones of the proposed antenna make it attractive for use in ultrawideband (UWB) systems.     

Switched parasitic antenna on a finite ground plane with conductive sleeve

A switched parasitic monopole antenna on a finite ground structure with a conductive sleeve attached to a small, circular ground plane controls the vertical radiation direction. The antenna was designed using a genetic algorithm and finite element (FEM) solver. At 1.575 GHz, the constructed antenna exhibited a front to back ratio of 10.7 dB and gain of 6.4 dBi with no elevation from the horizontal. The switched parasitic nature of the antenna allowed it to steer a directional beam through 5 locations in the azimuth. Incremented from 0/spl lambda/ to 0.45/spl lambda/, the sleeve was observed to linearly depress the main lobe elevation with little influence on other antenna characteristics such as gain and S/sub 11/.     

Compact CPW-fed dual-band antenna

A novel coplanar waveguide (CPW) antenna is proposed for dual-band WLAN applications. It comprises a rectangular patch, a rectangular notch cut at the lower edge of the patch and a CPW transmission line. The rectangular patch together with the ground plane of the coplanar waveguide radiates at the lower frequency band, 2.4 GHz for IEEE 802.11b/g, while the rectangular notch resonates in the upper band, 5.2/5.8 GHz for IEEE 802.11a. The designed antenna is only 32 × 5 mm, which can provide stable omnidirectional radiation patterns with an average gain of 2 dBi in both the bands. The antenna is very compact and suitable for 2.4 and 5.2/5.8 GHz WLAN operations.     

一种应用于WLAN的抗金属四频段平面单极天线设计

用于非金属外壳设备的常规天线与金属外壳设备一起使用,会导致完全不同的回波损耗。因此,提出了一种同时适用于金属外壳和非金属外壳设备的四频段平面单极天线,该天线由一个弯曲接地层、一对寄生贴片和由同轴馈电激发的辐射片组成。提出的天线能够在不同类型接地层影响下,保持其谐振频率一致性,甚至能够连接到金属外壳上。该天线适用于在WLAN 2.4/5.2/5.8 GHz、WiMAX 3.5/5.5 GHz和4.5GHz工作的多种应用。仿真和实际测量结果显示,即便是连接到较大的金属外壳或金属板时,提出天线能够较好地保持回波损耗和增益一致性且符合行业标准。     

用于WLAN的双频天线的设计与实现

提出了一种应用于无线局域网（WLAN）的新型双频天线。该天线采用微带线馈电的方法,其辐射面呈阶梯形,接地面为＂工＂型宽缝结构,可以覆盖IEEE802.11a/b/g（2.4～2.484GHz,5.15～5.825GHz）频段标准。其回波损耗小于10dB的阻抗带宽在2.4GHz频段可达160MHz（2.4～2.56GHz）,在5GHz频段的可达1.32GHz（5.05～6.37GHz）。整个天线在42mm×52mm、介电常数为4.5、厚度为1.5mm的FR4介质基片上实现。结果表明,该天线具有十分良好的应用潜质。     

Modified inverted-L monopole antenna for 2.4/5 GHz dual-band operations

A novel compact modified inverted-L monopole antenna for dual-band operation is proposed. The proposed antenna is designed to operate in 2.4 GHz (2400-2484 MHz) and 5 GHz (5150-5825 MHz) bands for WLAN applications in IEEE 802.11a/b and HIPERLAN/2 systems. The method to realise the desired dual-band operation is by introducing a meandered wire and a conducting triangular section to a conventional inverted-L monopole, which results in a small antenna size of 7/spl times/18 mm/sup 2/. Good impedance bandwidth performance is also observed.