Compact triple-band slotted monopole antenna with asymmetrical CPW grounds

By embedding slots into a rectangular patch a triple-band slotted monopole antenna fed by a coplanar waveguide (CPW) with two asymmetrical ground planes can be obtained. The designed antenna, which, including the ground plane, is only 9/spl times/20 mm/sup 2/, can excite resonant modes at 2.43, 5.23 and 7.14 GHz bands with measured impedance bandwidths of 14.4, 8.2 and 16.7%, and average antenna gains of /spl ges/2.4, 4.7 and 6.7 dBi, respectively. The antenna is very compact and suitable for 2.4/5.2 GHz WLAN operations.     

Analysis of the small band-rejected antenna with the parasitic strip for UWB

A novel band-rejected ultrawideband antenna with one parasitic strip is presented in this paper. It is designed to work on a substrate FR4 that has a thickness of 1 mm and relative permittivity of 4.6, and to operate from 3 to 17 GHz. The proposed antenna is fed by microstrip line and utilizes the parasitic strip to reject the frequency band (5.15-5.825 GHz) limited by IEEE 802.11a and HIPERLAN/2. The size of the antenna is 20/spl times/20 mm/sup 2/ and this antenna has good radiation characteristics. Effects of varying the location and length of the parasitic strip and the structure of the ground and monopole patch on the antenna performance have also been studied.     

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 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.     

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.     

Miniaturisation of microstrip patch antenna using perturbation of radiating slot

A highly miniaturised rectangular microstrip patch antenna using deformation of the patch structure has been designed and fabricated at a frequency of 1.575 GHz (GPS). The fabricated antenna has a patch with an overall rectangular shape and depressed at its four corners (corner depressed microstrip patch antenna, CDMPA). In the linear polarisation, at a fixed rate of 1.2 of width/length (W/L), the CDMPA (53/spl times/63.6 mm) is reduced to 43.9% of the general plane type microstrip patch antenna (MPA, 80/spl times/96 mm) in patch size. The gain is 4.3 dBd which is lower than that of the general MPA (8 dBd) by 3.7 dB. In the circular polarisation, the patch size of the CDMPA (54.2/spl times/61.5 mm) is reduced to 52.8% of that of the MPA (76/spl times/83 mm). The axial ratio (AR) and axial ratio band width (ARBW) within 2 dB are 1.5 dB and 20 MHz (1.27%), respectively. The gain is 2.5 dBd, which is lower than that (4.2 dBd) of the general MPA by 1.7 dB.     

Shorted, folded planar monopole antenna for dual-band mobile phone

A novel shorted, folded planar monopole antenna for application in GSM/DCS dual-band mobile phones is proposed. The antenna is easily fabricated from stamping a single metal plate, which is then folded onto a foam base of compact size 5/spl times/10/spl times/40 mm/sup 3/. In addition, the proposed antenna shows a very low profile of 5 mm protruded from the top edge of the system ground plane, making it very promising to be employed within the casing of a mobile phone as an internal antenna.     

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.     

Design of a planar inverted-F Antenna with very wide impedance bandwidth

This letter presents a novel wideband planar inverted F-antenna, which covers GSM850/DCS1800/DCS1900/ IMT2000/WLAN/DMB services at the same time. The proposed antenna consists of a main patch with a pair of slant slits and L-shaped patch and occupies a total volume of 15/spl times/44/spl times/8mm/sup 3/. The triple frequency bands are obtained by changing the length and width of a slant slit 1 on the main patch. A very wide impedance bandwidth characteristic is achieved by optimizing not only the length and height of a L-shaped patch between the main patch and ground plane but also the length and width of a pair of slits on the main patch which is excited by the modified coplanar waveguide-feed. Good broadside radiation patterns are achieved for all six-frequency bands of interest.     

Parallel plate waveguide antenna for point-to-multipoint communication at millimetre-wave frequencies

Simulation and measurement results for a parallel plate waveguide antenna designed for a point-to-multipoint communication system at millimetre-wave frequencies is presented. The antenna consists of a waveguide feed, an H-plane horn, an enclosed parabolic reflector, a rectangular waveguide containing irises, and corrugated baffles. Half power beamwidths between 4.9/spl deg/-6.0/spl deg/ in elevation and 58/spl deg/-79/spl deg/ in azimuth are achieved for a bandwidth of 13%. The gain varies between 19 and 20 dBi for the frequency range between 21 and 25 GHz. The manufactured antenna is very compact with a size of 200/spl times/147/spl times/50 mm.     

Reduced-size microstrip patch antenna for Bluetooth applications

A novel reduced-size microstrip rectangular patch antenna for Bluetooth operation is presented. The proposed antenna operates in the 2400-2484 MHz ISM band. Although an air substrate is introduced, the antenna occupies a small volume of 33.3/spl times/6.6/spl times/0.8 mm. The gain and the impedance bandwidth of the antenna are predicted using a commercial finite-element method software package. The predicted results show good agreement with measured data.     

Compact monopole antenna for GSM/DCS operation of mobile handsets

A novel dual-frequency monopole antenna, with a low profile and also with a small transverse size, is proposed. Firstly, by investigating and utilising a taper meander line antenna with a very large vertex angle, the antenna height is reduced to 15 mm. Secondly, by wrapping it in a box-like structure, the antenna transverse width is reduced to 12 mm. Thirdly, by introducing another geometrically complementary meander line branch, the second resonant mode is enhanced. Finally an antenna with dimensions of 15/spl times/12/spl times/7 mm is designed, and good impedance bandwidth performance for GSM (890-960 MHz) and DCS (1710-1880 MHz) bands is observed.     

A micromachined Pirani gauge with dual heat sinks

This paper reports a micromachined Pirani gauge with dual heat sinks that can be integrated with microelectromechanical systems (MEMS) devices inside a vacuum package to monitor long-term pressure changes and stability inside the package. The Pirani gauge utilizes small gaps (<1 /spl mu/m) between its heater and two thermal heat sinks to obtain large dynamic range (20 mtorr to 2 torr) and high sensitivity (3.5/spl times/10/sup 5/ (K/W)/torr). The gauge is 2/spl times/2 mm/sup 2/ in size, is fabricated using the dissolved wafer process (DWP) on a glass substrate, and utilizes dielectric bridges for signal routing. Measurements show the low end of the dynamic range can be extended by reducing the gap distance between the heater and thermal sinks, which matches well with analytical modeling. This gauge shows an uncertainty of 50 /spl mu/torr and a detectable leak rate of 3.1/spl times/10/sup -16/ cm/sup 3//s, assuming a common micropackage volume of 1.6/spl times/10/sup -5/ cm/sup 3/, which represents at least four orders of magnitude improvement over traditional leak testing.     

Multiple meander strip monopole antenna

A novel multiple meander strip monopole antenna is presented. By iteratively meandering the vertical strip, compactness and broadband characteristics for the monopole antenna were achieved simultaneously. The designed monopole antenna with a radiation element volume of 14/spl times/14/spl times/14 mm/sup 3/ has the measured bandwidth ratio of 3.87:1, from 2.83 to 10.96 GHz for VSWR/spl les/2, with fairly frequency-insensitive omni-directional radiation characteristics.     

Design for a Dual‐Frequency Antenna‐in‐Package

For an antenna‐in‐package (AiP), via holes are used to connect the antenna ground and system ground. In this letter, a dual‐frequency AiP with a U‐slot embedded in the patch is proposed. By properly arranging three via holes under the non‐radiating edge, an AiP with two resonant frequencies is realized. Then a U‐slot is embedded in the patch to further improve the bandwidth of the AiP. To validate the proposed design, an AiP with the bandwidth of 4.49% at 2.45 GHz and 6.02% at 5.32 GHz is achieved and fabricated. The measured results agree with the simulated results.     

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.     

Broadband CPW-fed folded-slot monopole antenna for 5.8 GHz RFID application

A folded slot is introduced to expand the impedance bandwidth and miniaturise the size of a coplanar waveguide (CPW)-fed patch monopole antenna for radio frequency identification (RFID) applications. The designed antenna, which, including ground plane, is only 13 mm in height and 11 mm in width, can operate at the 5.8 GHz band with measured impedance bandwidth and average antenna gain of 30% and /spl ges/5 dBi, respectively, and also conical radiation patterns. These properties make the antenna suitable for RFID tags.     

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.     

Compact wound-type slot antenna with wide bandwidth

A new type of a slot antenna in which a slot is formed in wound-type around a dielectric substrate is proposed. In comparison with a conventional meander slot antenna, the proposed antenna has a wider bandwidth and smaller size. The proposed antenna has been designed on a gallium arsenide (GaAs) substrate and fabricated by integrated circuit process for the integration of the antenna with active components. The fabricated antenna has dimensions of 6.2 /spl times/4.1 mm/sup 2/ and a 10-dB bandwidth of 300 MHz at 5.8 GHz.     

ICPA for highly integrated concurrent dual-band wireless receivers

A single-feed dual-band integrated circuit package antenna (ICPA) is reported. The ICPA, intended for use in either single-chip or single-package highly integrated concurrent dual-band wireless receivers, is implemented in the format of a cavity-down ceramic ball grid array package of 15/spl times/15/spl times/1.9 mm/sup 3/. Results show that the ICPA achieved a frequency ratio of 2.2, return loss bandwidth of 1.67% and gain of -8 dBi at 2.4 GHz, and return loss bandwidth of 0.69% and gain of -2 dBi at 5.25 GHz.