Two promising, internal, shorted monopole antennas for 700 MHz and WLAN/WiMAX operation are combined in an arrangement with minimized mutual coupling for palm-sized mobile applications. The two stamped, metal-plate antennas with a 2 mm gap therein between can be integrated into a compact configuration and are then mounted near one side of the system circuit board. With the suitable shorting locations and arrangement of the two antennas, good isolation (S21 < –20 dB) between the two ports can easily be obtained. Analysis of placing a CCD shielding cylinder between the two antennas and the two shorting strips joined to form a shorting wall are also conducted. Detailed designs of the two antennas are described, and the results thereof are discussed.
Hybrid of Monopole and Dipole Antennas for Concurrent 2.4- and 5-GHz WLAN Acc...Saou-Wen Su
A novel hybrid of a 2.4-GHz monopole antenna and a 5-GHz dipole antenna is presented to provide concurrent 2.4 and 5 GHz band operation for access- point applications. The two antennas are arranged in a collinear structure and printed on a compact dielectric substrate with dimensions 12 mm × 60 mm. The monopole antenna has a meandered radiating strip and is short-circuited to a small ground plane through a shorting strip. The dipole antenna includes two sub-dipoles at the opposite side of a narrow ground plane and fed by a simple T-junction microstrip-line network. The two antennas are closely set with a distance of 1 mm only, yet good port isolation (S21) well below –20 dB can be obtained. With a low profile, the proposed design can easily fit into the casing of some standard access points and allow the 2.4 and 5 GHz band signals to be simultaneously received or transmitted with no external diplexer required. Good omnidirectional radiation has been observed too.
Very-Low-Cost Copper-Wire Antenna for 2.4-GHz WLAN OperationSaou-Wen Su
A very-low-cost copper-wire antenna, easily fabricated by bending a single 70-mm-long copper wire two times, for WLAN operation in the 2.4 GHz band (2400-2484 MHz) is presented. The antenna has a very simple structure and is easily fed by using a 50- mini-coaxial cable. A prototype of the proposed antenna with the overall dimensions 40 mm x 5 mm is constructed and tested.
Printed Coplanar Two-Antenna Element for 2.4/5 GHz WLAN Operation in a MIMO S...Saou-Wen Su
A printed coplanar two-antenna element suited for WLAN operation in the 2.4 and 5 GHz bands for dual-module applications in a MIMO system is proposed. The two-antenna element is comprised of one planar inverted-F antenna (PIFA) and one monopole antenna, both printed and integrated in a coplanar configuration on a narrow dielectric substrate with the dimensions 50 mm × 11 mm. The two antennas are excited using two separate feeds with a common ground plane. By utilizing two proposed elements spaced 10 mm apart in the lateral direction with an optimized arrangement, the four-antenna MIMO system obtained can achieve optimal isolation between any two of the four antennas. In comparison with the conventional dual-band antenna with a single feed, the proposed two-antenna element allows the 2.4 and 5 GHz signals to be simultaneously received or transmitted with no external switch circuit between the antenna and modules required.
Low-Cost Flat Metal-Plate Dipole Antenna for 2.4/5 GHz WLAN OperationSaou-Wen Su
A low-cost, one-piece, flat-plate dipole antenna for dual WLAN band operation is presented. The dipole antenna is rectangular in shape with the dimensions 10 mm × 37 mm and fed by 50-ohm mini-coaxial cable. By cutting two L-shaped slits in each radiating arm, two dipole arms are obtained, which form a larger dipole and a smaller dipole antennas for the 2.4 and 5 GHz band operation respectively. The dipole arms are further short-circuited, making it possible for the antenna to be fabricated by stamping a single, flat metal plate only. The impedance bandwidth for 2.4/5 GHz WLAN operation is with VSWR below 1.5 and good omnidirectional radiation patterns are also observed.
2009 EuCAP-Hybrid of Monopole and Dipole Antennas for Concurrent WLAN APSaou-Wen Su
A novel hybrid of a 2.4-GHz monopole antenna and a 5-GHz dipole antenna is presented to provide concurrent 2.4 and 5 GHz band operation for access- point applications. The two antennas are arranged in a collinear structure and printed on a compact dielectric substrate with dimensions 12 mm × 60 mm. The monopole antenna has a meandered radiating strip and is short-circuited to a small ground plane through a shorting strip. The dipole antenna includes two sub-dipoles at the opposite side of a narrow ground plane and fed by a simple T-junction microstrip-line network. The two antennas are closely set with a distance of 1 mm only, yet good port isolation (S21) well below –20 dB can be obtained. With a low profile, the proposed design can easily fit into the casing of some standard access points and allow the 2.4 and 5 GHz band signals to be simultaneously received or transmitted with no external diplexer required. Good omnidirectional radiation has been observed too.
Compact Paper-Clip-Shaped Wire Antenna for 2.4 and 5.2 GHz WLAN OperationSaou-Wen Su
A compact dual-WLAN-band antenna, in the shape of a paper clip, is presented. The antenna can easily be manufactured by bending few times a single copper wire with a length of about 65 mm, and operates in the 2.4 and 5.2 GHz bands in the WLAN environment. In addition to the simple configuration, the antenna is easily fed by 50- mini-coaxial cable, which allows it flexibility in a defined location for installation. An experimental prototype of the proposed antenna with the overall dimensions about 5 mm x 23.5 mm is constructed, tested, and demonstrated.
An Internal Wideband Monopole Antenna for UMTS/WLAN Dual-Mode Mobile PhoneSaou-Wen Su
An internal wideband metal-plate monopole antenna for mobile phone applications is presented. The antenna is easily fabricated by bending a single metal plate and suitable to be embedded within the casing of a mobile phone as an internal antenna. Further, the antenna shows a wide operating bandwidth of about 5 GHz (about 1.8−6.7 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 for a mobile phone.
Printed Omnidirectional Access-Point Antenna for 2.4/5-GHz WLAN OperationSaou-Wen Su
A new design of the printed omnidirectional antenna for applications in 2.4/5-GHz dual-WLAN-band access points is proposed. The antenna consists of a conventional collinear antenna for 2.4 GHz operation and two U stubs for 5 GHz operation. The two U stubs are located near the points where the maximum currents at about 5.5 GHz occurring on the strips of the collinear antenna, and arranged back to back in the same phase for achieving better antenna gain. Detailed analyses of the U stub on the impedance matching over the 5 GH band is presented. A prototype with good omnidirectional radiation across the 2.4/5-GHz WLAN bands is demonstrated.
Hybrid of Monopole and Dipole Antennas for Concurrent 2.4- and 5-GHz WLAN Acc...Saou-Wen Su
A novel hybrid of a 2.4-GHz monopole antenna and a 5-GHz dipole antenna is presented to provide concurrent 2.4 and 5 GHz band operation for access- point applications. The two antennas are arranged in a collinear structure and printed on a compact dielectric substrate with dimensions 12 mm × 60 mm. The monopole antenna has a meandered radiating strip and is short-circuited to a small ground plane through a shorting strip. The dipole antenna includes two sub-dipoles at the opposite side of a narrow ground plane and fed by a simple T-junction microstrip-line network. The two antennas are closely set with a distance of 1 mm only, yet good port isolation (S21) well below –20 dB can be obtained. With a low profile, the proposed design can easily fit into the casing of some standard access points and allow the 2.4 and 5 GHz band signals to be simultaneously received or transmitted with no external diplexer required. Good omnidirectional radiation has been observed too.
Very-Low-Cost Copper-Wire Antenna for 2.4-GHz WLAN OperationSaou-Wen Su
A very-low-cost copper-wire antenna, easily fabricated by bending a single 70-mm-long copper wire two times, for WLAN operation in the 2.4 GHz band (2400-2484 MHz) is presented. The antenna has a very simple structure and is easily fed by using a 50- mini-coaxial cable. A prototype of the proposed antenna with the overall dimensions 40 mm x 5 mm is constructed and tested.
Printed Coplanar Two-Antenna Element for 2.4/5 GHz WLAN Operation in a MIMO S...Saou-Wen Su
A printed coplanar two-antenna element suited for WLAN operation in the 2.4 and 5 GHz bands for dual-module applications in a MIMO system is proposed. The two-antenna element is comprised of one planar inverted-F antenna (PIFA) and one monopole antenna, both printed and integrated in a coplanar configuration on a narrow dielectric substrate with the dimensions 50 mm × 11 mm. The two antennas are excited using two separate feeds with a common ground plane. By utilizing two proposed elements spaced 10 mm apart in the lateral direction with an optimized arrangement, the four-antenna MIMO system obtained can achieve optimal isolation between any two of the four antennas. In comparison with the conventional dual-band antenna with a single feed, the proposed two-antenna element allows the 2.4 and 5 GHz signals to be simultaneously received or transmitted with no external switch circuit between the antenna and modules required.
Low-Cost Flat Metal-Plate Dipole Antenna for 2.4/5 GHz WLAN OperationSaou-Wen Su
A low-cost, one-piece, flat-plate dipole antenna for dual WLAN band operation is presented. The dipole antenna is rectangular in shape with the dimensions 10 mm × 37 mm and fed by 50-ohm mini-coaxial cable. By cutting two L-shaped slits in each radiating arm, two dipole arms are obtained, which form a larger dipole and a smaller dipole antennas for the 2.4 and 5 GHz band operation respectively. The dipole arms are further short-circuited, making it possible for the antenna to be fabricated by stamping a single, flat metal plate only. The impedance bandwidth for 2.4/5 GHz WLAN operation is with VSWR below 1.5 and good omnidirectional radiation patterns are also observed.
2009 EuCAP-Hybrid of Monopole and Dipole Antennas for Concurrent WLAN APSaou-Wen Su
A novel hybrid of a 2.4-GHz monopole antenna and a 5-GHz dipole antenna is presented to provide concurrent 2.4 and 5 GHz band operation for access- point applications. The two antennas are arranged in a collinear structure and printed on a compact dielectric substrate with dimensions 12 mm × 60 mm. The monopole antenna has a meandered radiating strip and is short-circuited to a small ground plane through a shorting strip. The dipole antenna includes two sub-dipoles at the opposite side of a narrow ground plane and fed by a simple T-junction microstrip-line network. The two antennas are closely set with a distance of 1 mm only, yet good port isolation (S21) well below –20 dB can be obtained. With a low profile, the proposed design can easily fit into the casing of some standard access points and allow the 2.4 and 5 GHz band signals to be simultaneously received or transmitted with no external diplexer required. Good omnidirectional radiation has been observed too.
Compact Paper-Clip-Shaped Wire Antenna for 2.4 and 5.2 GHz WLAN OperationSaou-Wen Su
A compact dual-WLAN-band antenna, in the shape of a paper clip, is presented. The antenna can easily be manufactured by bending few times a single copper wire with a length of about 65 mm, and operates in the 2.4 and 5.2 GHz bands in the WLAN environment. In addition to the simple configuration, the antenna is easily fed by 50- mini-coaxial cable, which allows it flexibility in a defined location for installation. An experimental prototype of the proposed antenna with the overall dimensions about 5 mm x 23.5 mm is constructed, tested, and demonstrated.
An Internal Wideband Monopole Antenna for UMTS/WLAN Dual-Mode Mobile PhoneSaou-Wen Su
An internal wideband metal-plate monopole antenna for mobile phone applications is presented. The antenna is easily fabricated by bending a single metal plate and suitable to be embedded within the casing of a mobile phone as an internal antenna. Further, the antenna shows a wide operating bandwidth of about 5 GHz (about 1.8−6.7 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 for a mobile phone.
Printed Omnidirectional Access-Point Antenna for 2.4/5-GHz WLAN OperationSaou-Wen Su
A new design of the printed omnidirectional antenna for applications in 2.4/5-GHz dual-WLAN-band access points is proposed. The antenna consists of a conventional collinear antenna for 2.4 GHz operation and two U stubs for 5 GHz operation. The two U stubs are located near the points where the maximum currents at about 5.5 GHz occurring on the strips of the collinear antenna, and arranged back to back in the same phase for achieving better antenna gain. Detailed analyses of the U stub on the impedance matching over the 5 GH band is presented. A prototype with good omnidirectional radiation across the 2.4/5-GHz WLAN bands is demonstrated.
Concurrent 2.4/5-GHz Multi-Loop MIMO Antennas with Wide 3-dB Beamwidth Radiat...Saou-Wen Su
A high-gain, wide-beamwidth, six-loop-antenna MIMO system suited for wireless access points in the concurrent WLAN 2.4 and 5 GHz bands is presented. The antenna system mainly comprises an antenna ground plane and single-band loop antennas, among which the three antennas are designated for 2.4 and 5 GHz operation respectively. The antennas are set in a sequential, rotating arrangement on the ground plane with an equal inclination angle of 60° to form a symmetrical structure, and the 2.4 and 5 GHz loops are facing each other one by one. The experimental results show that good port isolation can be obtained between antenna ports. High-gain, directional radiation patterns with wide 3-dB beamwidth in elevation planes are also observed. Details of a design prototype are described and discussed in the paper.
Realization of Dual-Dipole-Antenna System for Concurrent Dual-Radio Operation...Saou-Wen Su
The study of the mutual coupling between the two simple strip dipole antennas is first carried out and investigated. The results show that the coupling or the antenna port isolation is almost separation distance independent when the two dipole antennas are arranged to be of orthogonal polarization. Following this characteristic, a novel dual-dipole-antenna system aimed for concurrent 2.4 and 5 GHz band operation and at the same time, to achieve very compact integration of two individual antennas with separate feeds is proposed. The two dipole antennas are etched on a two-layered dielectric substrate with dimensions 30 mm × 30 mm. On the front layer is put the 2.4 GHz dipole, which is perpendicular to the 5 GHz dipole located on the bottom layer. Though the two dipoles are stacked up with a distance of 0.8 mm only, port isolation can still be below –15 dB. The proposed dual-dipole-antenna system is a promising candidate for the antenna solution that enables simultaneous dual-radio operation.
A Bent, Shorted, Planar Monopole Antenna for 2.4 GHz WLAN ApplicationsSaou-Wen Su
A simple, bent monopole antenna well useful for WLAN applications in the 2.4 GHz band is presented. The monopole antenna has a rectangular radiating plate in general and is short-circuited to a small antenna ground and an assembly plate. The assembly plate is not only used as a supporting plate for antenna installation but also regarded as antenna ground. With a low profile of the monopole and use of the coaxial-line feed, the antenna has much flexibility in the placement inside a wireless device. Good radiation characteristics have been observed too.
Very-Low-Profile Monopole Antennas for Concurrent 2.4- and 5-GHz WLAN Access-...Saou-Wen Su
A very-low-profile, six-antenna MIMO system aimed at operating in the concurrent 2.4 and 5 GHz bands for WLAN access-point applications is proposed. The MIMO system consists mainly of an antenna ground plane and six short-circuited monopole antennas, among which the three antennas are designated for 2.4 and 5 GHz operation respectively. The antennas are set in a sequential, rotating arrangement on the ground plane, and the 2.4 and 5 GHz antennas are facing each other one by one. The results show that well port isolation can be obtained together with good radiation characteristics. With a low profile of 6 mm in height, the proposed design can easily fit into wireless access points or routers and allow the 2.4- and 5-GHz band signals to be simultaneously received and transmitted with no need of external diplexer.
2008 IEEE AP-S-Internal Wideband Monopole Antenna For MIMO Access-Point Appli...Saou-Wen Su
A three-antenna MIMO system capable of generating a wide operating bandwidth of 2400-5850 MHz for access-point applications is introduced. The proposed design is based on a bent metal-plate monopole antenna with a compact size of 20 × 20 × 14 mm3. The three antennas are equally spaced along the perimeter of a circular ground and all generate a wide bandwidth of larger than 4 GHz. With the antenna short-circuiting facing the center of the ground, not only the overall antenna size is reduced but also good isolation of less than -20 dB can easily be obtained. Calculated envelope correlation is also less than 0.002 across the operating band.
Compact Vertical Patch Antenna for Dual-Band WLAN OperationSaou-Wen Su
A new compact patch antenna, which is arranged perpendicular to a circular ground plane, for WLAN operation is presented. The antenna consists mainly of one driven patch and one shorted parasitic patch, which both wind along two concentric circles. A constructed prototype covering the 2.4 and 5 GHz WLAN bands is demonstrated. Good broadside radiation characteristics are obtained across the operating bands. Details of the proposed patch antenna and experimental results are presented and discussed.
A Review of Multi Resonant Slotted Micro Strip Patch Antenna (MPA) for IMT, W...IJEEE
In this paper, a stacked multi resonant slotted micro strip patch antenna (MPA) has been proposed which is suitable to be used for GSM, WLAN standard and WiMAX applications. The antenna has been designed using substrate of FR4 material. In the designed stacked antenna, substrates having different thickness has been used. The bottom stack of designed antenna has a radiating patch of circular shape and the patch on the upper stack has rectangular shape and is flexible in nature. The antenna has a feed line which is connected to circular patch to feed power to the antenna. The feed line has to be of suitable width to match the antenna impedance with port impedance of 50 ohms. The designed antenna has a defected ground structure in order to improve the antenna performance. The antenna performance has been measured in terms of antenna parameters such as impedance bandwidth (GHz), Return loss (dB), antenna impedance (ohms), VSWR and Directivity (dBi). The designed antenna results have been simulated in CST Microwave Studio 2010. The practically designed antenna has been tested successfully by using Network analyzer E5071C. It has been observed that the practical results closely match with theoretical results.
2009 IEEE AP-S-Compact Coaxial-Line-Fed Printed Monopole Antenna for Lower-Ba...Saou-Wen Su
A compact, printed, ultrawideband (UWB) monopole antenna suitable to be as an internal antenna attractive for future UWB applications is demonstrated. The proposed antenna is of a small form factor with the dimensions 6 mm × 33 mm and can easily be fed by 50-ohms mini-cable line. The antenna mainly comprises a monopole antenna, a feeding strip and a ground plane, all printed on a small FR4 substrate. The monopole antenna is printed on both layers of the substrate with an end portion on the back for control of the first/lower resonant mode of the antenna. The feeding strip in between the monopole antenna and the ground plane is further offset to achieve better impedance matching and proper upper-edge operating frequency. With the proposed antenna structure, which provides an operating bandwidth of larger than 2.7 GHz, the impedance bandwidth by 10-dB return loss can easily cover the 3.1–4.85 GHz band, the lower band of the UWB operation.
Internal Wideband Monopole Antenna for MIMO Access-Point Applications in the ...Saou-Wen Su
A three-antenna MIMO system capable of generating a wide operating bandwidth of 2400-5850 MHz for access-point applications is introduced. The proposed design is based on a bent metal-plate monopole antenna with a compact size of 20 × 20 × 14 mm3. The three antennas are equally spaced along the perimeter of a circular ground and all generate a wide bandwidth of larger than 4 GHz. With the antenna short-circuiting facing the center of the ground, not only the overall antenna size is reduced but also good isolation of less than -20 dB can easily be obtained. Calculated envelope correlation is also less than 0.002 across the operating band. The design prototype of the antenna is discussed in detail in the paper.
Design of a Dual-Band Microstrip Patch Antenna for GPS,WiMAX and WLAN.IOSR Journals
The A multi band microstrip patch antenna has been designed for GPS,WiMAX and WLAN
applications. The proposed antenna is designed by using substrate of RT duroid having permittivity of about 2.2
and loss tangent of 1.The substrate is having thickness of 6mm at which a trapezoidal patch antenna with V slot
has been introduced in this paper. The designing results like S11 parameter return loss,VSWR and field pattern
is plotted successfully. The obtained result is having a two band resonance with S11 less then -10dB and VSWR
less than 2.
So a dual band trapezoidal microstrip patch antenna has been designed and all results are plotted.Simmulating
software used is IE3D.
IJERA (International journal of Engineering Research and Applications) is International online, ... peer reviewed journal. For more detail or submit your article, please visit www.ijera.com
Design of Reconfigurable Microstrip Patch Antenna for WLAN ApplicationEditor IJMTER
In this paper we propose a rectangular microstrip patch antenna with inset fed which can
operate at 2.4 GHz (IEEE 802.11b) & 5.8 GHz (IEEE 802.11a) WLAN applications. Various slot is
cut into the antenna structure which changes the surface current path resulting in dual resonant
frequency. Further by embedding any switch into a slot, reconfiguration can be achieved i.e. the
antenna can only be used in unlicensed 2.4 GHz band. The achieved directivity is greater than 5db and
the bandwidth obtained is much greater than the required bandwidth. The proposed antenna is
simulated using High Frequency Structure Simulator.
A Three-in-One Diversity Antenna System for 5 GHz WLAN ApplicationsSaou-Wen Su
A novel, three-in-one antenna system suitable for WLAN operation in the 5 GHz band is presented. The design is based upon incorporating one slot and two dipole antennas into a compact multi-antenna system that has comparable dimensions of a single mobile-unit antenna element. The three antennas are arranged parallel to each other with the two dipoles set on the right and left sides of the slot respectively. With this arrangement, not only can compact integration of three individual antennas be realized, pattern diversity and polarization diversity are also obtained. A design prototype has been constructed and tested. The results show that the coupling or the antenna port isolation is below –20 dB and good radiation characteristics have been observed.
This work presents a rectangular of microstrip ultra wideband patch antenna for worldwide interoperability for microwave access (Wi-Max) and wireless local area network (WLAN) with a dual band-notched feature. The planned an antenna consists the rectangular of patch antenna with the largely deficient of ground structure. Through inserting slots in the radiating patch, dual notch characteristics may be produced. The suggested antenna is 20×30×1.6 mm3 in volume. The first notch, made by slots operating at the first notch, produced by slots running at 3.5 GHz, for Wi-Max (from 3.3-3.7 GHz), while of a second, created by slots operating at 5.5 GHz, for WLAN (from 5.1-5.8 GHz). An antenna covers the whole ultra-wideband frequency range (3.1-10.6 GHz). Computer simulation technology (CST) 2021 simulation software used for simulate proposed of antenna. A simulated antenna’s emission pattern is almost omnidirectional, and the recommended antenna’s gain is approximately constant over the ultra-wideband (UWB) spectrum, excluding notch areas.
Concurrent 2.4/5-GHz Multi-Loop MIMO Antennas with Wide 3-dB Beamwidth Radiat...Saou-Wen Su
A high-gain, wide-beamwidth, six-loop-antenna MIMO system suited for wireless access points in the concurrent WLAN 2.4 and 5 GHz bands is presented. The antenna system mainly comprises an antenna ground plane and single-band loop antennas, among which the three antennas are designated for 2.4 and 5 GHz operation respectively. The antennas are set in a sequential, rotating arrangement on the ground plane with an equal inclination angle of 60° to form a symmetrical structure, and the 2.4 and 5 GHz loops are facing each other one by one. The experimental results show that good port isolation can be obtained between antenna ports. High-gain, directional radiation patterns with wide 3-dB beamwidth in elevation planes are also observed. Details of a design prototype are described and discussed in the paper.
Realization of Dual-Dipole-Antenna System for Concurrent Dual-Radio Operation...Saou-Wen Su
The study of the mutual coupling between the two simple strip dipole antennas is first carried out and investigated. The results show that the coupling or the antenna port isolation is almost separation distance independent when the two dipole antennas are arranged to be of orthogonal polarization. Following this characteristic, a novel dual-dipole-antenna system aimed for concurrent 2.4 and 5 GHz band operation and at the same time, to achieve very compact integration of two individual antennas with separate feeds is proposed. The two dipole antennas are etched on a two-layered dielectric substrate with dimensions 30 mm × 30 mm. On the front layer is put the 2.4 GHz dipole, which is perpendicular to the 5 GHz dipole located on the bottom layer. Though the two dipoles are stacked up with a distance of 0.8 mm only, port isolation can still be below –15 dB. The proposed dual-dipole-antenna system is a promising candidate for the antenna solution that enables simultaneous dual-radio operation.
A Bent, Shorted, Planar Monopole Antenna for 2.4 GHz WLAN ApplicationsSaou-Wen Su
A simple, bent monopole antenna well useful for WLAN applications in the 2.4 GHz band is presented. The monopole antenna has a rectangular radiating plate in general and is short-circuited to a small antenna ground and an assembly plate. The assembly plate is not only used as a supporting plate for antenna installation but also regarded as antenna ground. With a low profile of the monopole and use of the coaxial-line feed, the antenna has much flexibility in the placement inside a wireless device. Good radiation characteristics have been observed too.
Very-Low-Profile Monopole Antennas for Concurrent 2.4- and 5-GHz WLAN Access-...Saou-Wen Su
A very-low-profile, six-antenna MIMO system aimed at operating in the concurrent 2.4 and 5 GHz bands for WLAN access-point applications is proposed. The MIMO system consists mainly of an antenna ground plane and six short-circuited monopole antennas, among which the three antennas are designated for 2.4 and 5 GHz operation respectively. The antennas are set in a sequential, rotating arrangement on the ground plane, and the 2.4 and 5 GHz antennas are facing each other one by one. The results show that well port isolation can be obtained together with good radiation characteristics. With a low profile of 6 mm in height, the proposed design can easily fit into wireless access points or routers and allow the 2.4- and 5-GHz band signals to be simultaneously received and transmitted with no need of external diplexer.
2008 IEEE AP-S-Internal Wideband Monopole Antenna For MIMO Access-Point Appli...Saou-Wen Su
A three-antenna MIMO system capable of generating a wide operating bandwidth of 2400-5850 MHz for access-point applications is introduced. The proposed design is based on a bent metal-plate monopole antenna with a compact size of 20 × 20 × 14 mm3. The three antennas are equally spaced along the perimeter of a circular ground and all generate a wide bandwidth of larger than 4 GHz. With the antenna short-circuiting facing the center of the ground, not only the overall antenna size is reduced but also good isolation of less than -20 dB can easily be obtained. Calculated envelope correlation is also less than 0.002 across the operating band.
Compact Vertical Patch Antenna for Dual-Band WLAN OperationSaou-Wen Su
A new compact patch antenna, which is arranged perpendicular to a circular ground plane, for WLAN operation is presented. The antenna consists mainly of one driven patch and one shorted parasitic patch, which both wind along two concentric circles. A constructed prototype covering the 2.4 and 5 GHz WLAN bands is demonstrated. Good broadside radiation characteristics are obtained across the operating bands. Details of the proposed patch antenna and experimental results are presented and discussed.
A Review of Multi Resonant Slotted Micro Strip Patch Antenna (MPA) for IMT, W...IJEEE
In this paper, a stacked multi resonant slotted micro strip patch antenna (MPA) has been proposed which is suitable to be used for GSM, WLAN standard and WiMAX applications. The antenna has been designed using substrate of FR4 material. In the designed stacked antenna, substrates having different thickness has been used. The bottom stack of designed antenna has a radiating patch of circular shape and the patch on the upper stack has rectangular shape and is flexible in nature. The antenna has a feed line which is connected to circular patch to feed power to the antenna. The feed line has to be of suitable width to match the antenna impedance with port impedance of 50 ohms. The designed antenna has a defected ground structure in order to improve the antenna performance. The antenna performance has been measured in terms of antenna parameters such as impedance bandwidth (GHz), Return loss (dB), antenna impedance (ohms), VSWR and Directivity (dBi). The designed antenna results have been simulated in CST Microwave Studio 2010. The practically designed antenna has been tested successfully by using Network analyzer E5071C. It has been observed that the practical results closely match with theoretical results.
2009 IEEE AP-S-Compact Coaxial-Line-Fed Printed Monopole Antenna for Lower-Ba...Saou-Wen Su
A compact, printed, ultrawideband (UWB) monopole antenna suitable to be as an internal antenna attractive for future UWB applications is demonstrated. The proposed antenna is of a small form factor with the dimensions 6 mm × 33 mm and can easily be fed by 50-ohms mini-cable line. The antenna mainly comprises a monopole antenna, a feeding strip and a ground plane, all printed on a small FR4 substrate. The monopole antenna is printed on both layers of the substrate with an end portion on the back for control of the first/lower resonant mode of the antenna. The feeding strip in between the monopole antenna and the ground plane is further offset to achieve better impedance matching and proper upper-edge operating frequency. With the proposed antenna structure, which provides an operating bandwidth of larger than 2.7 GHz, the impedance bandwidth by 10-dB return loss can easily cover the 3.1–4.85 GHz band, the lower band of the UWB operation.
Internal Wideband Monopole Antenna for MIMO Access-Point Applications in the ...Saou-Wen Su
A three-antenna MIMO system capable of generating a wide operating bandwidth of 2400-5850 MHz for access-point applications is introduced. The proposed design is based on a bent metal-plate monopole antenna with a compact size of 20 × 20 × 14 mm3. The three antennas are equally spaced along the perimeter of a circular ground and all generate a wide bandwidth of larger than 4 GHz. With the antenna short-circuiting facing the center of the ground, not only the overall antenna size is reduced but also good isolation of less than -20 dB can easily be obtained. Calculated envelope correlation is also less than 0.002 across the operating band. The design prototype of the antenna is discussed in detail in the paper.
Design of a Dual-Band Microstrip Patch Antenna for GPS,WiMAX and WLAN.IOSR Journals
The A multi band microstrip patch antenna has been designed for GPS,WiMAX and WLAN
applications. The proposed antenna is designed by using substrate of RT duroid having permittivity of about 2.2
and loss tangent of 1.The substrate is having thickness of 6mm at which a trapezoidal patch antenna with V slot
has been introduced in this paper. The designing results like S11 parameter return loss,VSWR and field pattern
is plotted successfully. The obtained result is having a two band resonance with S11 less then -10dB and VSWR
less than 2.
So a dual band trapezoidal microstrip patch antenna has been designed and all results are plotted.Simmulating
software used is IE3D.
IJERA (International journal of Engineering Research and Applications) is International online, ... peer reviewed journal. For more detail or submit your article, please visit www.ijera.com
Design of Reconfigurable Microstrip Patch Antenna for WLAN ApplicationEditor IJMTER
In this paper we propose a rectangular microstrip patch antenna with inset fed which can
operate at 2.4 GHz (IEEE 802.11b) & 5.8 GHz (IEEE 802.11a) WLAN applications. Various slot is
cut into the antenna structure which changes the surface current path resulting in dual resonant
frequency. Further by embedding any switch into a slot, reconfiguration can be achieved i.e. the
antenna can only be used in unlicensed 2.4 GHz band. The achieved directivity is greater than 5db and
the bandwidth obtained is much greater than the required bandwidth. The proposed antenna is
simulated using High Frequency Structure Simulator.
A Three-in-One Diversity Antenna System for 5 GHz WLAN ApplicationsSaou-Wen Su
A novel, three-in-one antenna system suitable for WLAN operation in the 5 GHz band is presented. The design is based upon incorporating one slot and two dipole antennas into a compact multi-antenna system that has comparable dimensions of a single mobile-unit antenna element. The three antennas are arranged parallel to each other with the two dipoles set on the right and left sides of the slot respectively. With this arrangement, not only can compact integration of three individual antennas be realized, pattern diversity and polarization diversity are also obtained. A design prototype has been constructed and tested. The results show that the coupling or the antenna port isolation is below –20 dB and good radiation characteristics have been observed.
This work presents a rectangular of microstrip ultra wideband patch antenna for worldwide interoperability for microwave access (Wi-Max) and wireless local area network (WLAN) with a dual band-notched feature. The planned an antenna consists the rectangular of patch antenna with the largely deficient of ground structure. Through inserting slots in the radiating patch, dual notch characteristics may be produced. The suggested antenna is 20×30×1.6 mm3 in volume. The first notch, made by slots operating at the first notch, produced by slots running at 3.5 GHz, for Wi-Max (from 3.3-3.7 GHz), while of a second, created by slots operating at 5.5 GHz, for WLAN (from 5.1-5.8 GHz). An antenna covers the whole ultra-wideband frequency range (3.1-10.6 GHz). Computer simulation technology (CST) 2021 simulation software used for simulate proposed of antenna. A simulated antenna’s emission pattern is almost omnidirectional, and the recommended antenna’s gain is approximately constant over the ultra-wideband (UWB) spectrum, excluding notch areas.
A miniaturized hairpin resonator for the high selectivity of WLAN bandwidthjournalBEEI
In this article, a miniaturized hairpin resonator has been presented to introduce the high selectivity of Wireless Local Area Network (WLAN) bandwidth. In the construction of the hairpin resonator, short-circuited
comb-lines are electrically coupled with the two longer edges of a rectangular-shaped loop. The hairpin resonator has been designed and fabricated with the Taconic TLX-8 substrate with a center-frequency at 2.45 GHz. The resonator exhibits a second order quasi-Chebyshev bandpass response. A low insertion loss has been found as -0.36 dB with a minimum return loss as -36.71 dB. The filtering dimension of this hairpin resonator occupies a small area of 166.82 mm2. This hairpin resonator is highly selective for the bandpass applications of the entire WLAN bandwidth.
A compact dual-band semi-flexible antenna at 2.45 GHz and 5.8 GHz for wearabl...journalBEEI
In this work, a compact dual-band semi-flexible antenna operating at 2.45 GHz and 5.8 GHz for the industrial, scientific and medical (ISM) band is presented. The antenna is fabricated on a semi-flexible substrate material, Rogers Duroid RO3003™ with a low-profile feature with dimensions of 30×38 mm2 which makes it a good solution for wearable applications. Bending investigation is also performed over a vacuum cylinder and the diameters are varied at 50 mm, 80 mm and 100 mm, that represents the average human arm’s diameter. The bending investigation shows that reflection coefficients for all diameters are almost similar which imply that the antenna will operate at the dual-band resonant frequencies, even in bending condition. The simulated specific absorption rate (SAR) in CST MWS® software shows that the antenna obeys the FCC and ICNIRP guidelines for 1 mW of input power. The SAR limits at 2.45 GHz for 1 g of human tissue is simulated at 0.271 W/kg (FCC standard: 1.6 W/kg) while for 10 g is at 0.0551 W/kg (ICNIRP standard: 2 W/kg. On the other hand, the SAR limits at 5.8 GHz are computed at 0.202 W/kg for 1 g and 0.0532 W/kg for 10 g.
Multiband Circular Microstrip Patch Antenna for WLAN Applicationtheijes
The International Journal of Engineering & Science is aimed at providing a platform for researchers, engineers, scientists, or educators to publish their original research results, to exchange new ideas, to disseminate information in innovative designs, engineering experiences and technological skills. It is also the Journal's objective to promote engineering and technology education. All papers submitted to the Journal will be blind peer-reviewed. Only original articles will be published.
5G Fixed Beam Switching on Microstrip Patch Antenna IJECEIAES
5G technology is using millimeter-wave band to improve the wireless communication system. However, narrow transmitter and receiver beams have caused the beam coverage area to be limited. Due to propagation limitations of mm wave band, beam forming technology with multi-beam based communication system, has been focused to overcome the problem. In this letter, a fixed beam switching method is introduced. By changing the switches, four different configurations of patch array antennas are designed to investigate their performances in terms of radiation patterns, beam forming angle, gain, half-power bandwidth and impedance bandwidth at 28 GHz operating frequency for 5G application. Mircostrip antenna is preferred due to its low profile, easy in feeding and array configurations. Three different beam directions had been formed at -15°, 0°, and 15° with half-power bandwidth of range 45˚ to 50˚.
We recommend a circular monopole antenna (CMPA) with a central feed to operate in three bands. The antenna is circular and has an 8 cm diameter. The suggested antennas' resonance frequency ranges are 2.43 GHz, 5.24 GHz, and 9.61 GHz. The planned CMPA is made up of two circle-shaped slots cut into the radiating patch. The whole structure is supplied via a microstrip feed line and analysed using CST Studio's electromagnetic simulator, which is based on finite integral technique (FIT). To check the structure, the return loss, radiation pattern, voltage standing wave ratio (VSWR), and gain are all examined. The structure's ideal dimensions are determined using a parametric study of three factors: feed position, feed breadth, and ground size. The proposed CMPA is capable of operating in several bands and has good matching impedance in all of them.
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Our journal system primarily aims to bring out the research talent and the works done by sciaentists, academia, engineers, practitioners, scholars, post graduate students of engineering and science. This journal aims to cover the scientific research in a broader sense and not publishing a niche area of research facilitating researchers from various verticals to publish their papers. It is also aimed to provide a platform for the researchers to publish in a shorter of time, enabling them to continue further All articles published are freely available to scientific researchers in the Government agencies,educators and the general public. We are taking serious efforts to promote our journal across the globe in various ways, we are sure that our journal will act as a scientific platform for all researchers to publish their works online.
Switchable dual-band bandpass filter based on stepped impedance resonator wit...TELKOMNIKA JOURNAL
This paper presents a new technique in designing the switchable dual-band bandpass filter at
2.4 GHz and 3.5 GHz for WLAN and WiMAX applications. Wideband bandpass filter designed based on
stepped impedance resonator at frequency of 3 GHz. To eliminate the interference from existing system
that operates in the same frequency band, a defected microstrip structure applied and implemented to
produce the notch response. In order to generate the switchable characteristic, the PIN diode was
introduced at the dual-band filter. It exhibits that the measured results for switchable attributes when the
diode is at OFF state, the wide passband is produced with the fractional bandwidth of 62.1 % centered at
2.9 GHz. Meanwhile, for the diode in ON state, the dual-passband has produced which centered at
2.5 GHz and 3.45 GHz. The experimental results showed good agreement with the simulation results. This
structure is very useful for wireless communication systems and its applications.
Prediction of path loss in a wireless system is important to determine its quality of service. Fluctuations
and variations of signal strength at higher frequency range in Near Field zone, is a common difficulty to
achieve higher data rate. Continuous variation in signal causes decay of strength by the interference of the
atmospheric obstructions and hence electric field intensity gradually decreases with the distance. In this
paper the behaviour of field strength is explored through AWAS Electromagnetic Code which predicts the
rapid variations in electric field intensity irrespective of environment as compare to statistical models
which do not capture the variations as per Environment. An adequate and optimum values of these
parameters is essential for efficient transmission. The results show that the numerical analysis predicts
much lower field strengths which could significantly affect the channel quality. . This investigation is
essential to reduce the rapid fluctuations in field strength of the WiMAX.
Semi-circular compact CPW-fed antenna for ultra-wideband applicationsTELKOMNIKA JOURNAL
This paper presents a simple structure and small size antenna design with dimensions of 43×47 mm2 to perform an ultra-wideband (UWB) frequency range using a semicircular co-planar waveguide (CPW). This antenna has been designed and simulated by the computer simulation technology (CST) microwave studio suit. In this work, we design an ultra-wideband antenna (about 2 GHz to 10 GHz) by feeding a semi-circular compact antenna via a co-planar waveguide for input impedance of 50 Ω. The CST simulation results show that our designed antenna has a very good impedance and radiation characteristic within the intended ultra-wideband. Because of the small size and the suitable shape, this antenna can be used in many wireless communication applications, such as a radio frequency identifier (RFID), indoor wireless local area network or wireless fidelity (WiFi), internet of things (IoT), millimeter waves communications (mmWave), global positioning system (GPS), and many applications of 6G systems.
Substrate integrate waveguide and microstrip antennas at 28 GHzjournalBEEI
In this paper, two antennas are designed using substrate integrated waveguide (SIW) and microstrip technology at 28 GHz. Parametric study for both antennas is presented to demonstrate the performance at millimeter wave frequency for wireless communication network (5G application). Roger RT5880 substrates with permittivity 2.2 and loss tangent 0.0009 are used to implement the antennas with two thicknesses of 0.508 mm and 0.127 mm respectively. Both antennas have the same size of substrate 12x12 mm with a full ground plane was used. Structures designs have been done by using computer simulation technology (CST). The simulation results showed that the antenna with SIW and roger RT 5880 substrate thickness 0.508 has better performance in term of return loss and radiation pattern than the microstrip patch antenna at 28 GHz. A return loss more than -10 dB and the gain are 6.4 dB obtained with wide bandwidth range of (27.4-28.7) GHz. This proving to increase the realized gain by implementing SIW at millimeter wave band for 5G application network.
A One-Piece Flat-Plate Dipole Antenna for Dual-Band WLAN OperationSaou-Wen Su
A simple, one-piece, flat-plate dipole antenna suitable for dual-band WLAN applications is presented. The antenna is structured to be of an L shape to fit in corners of possible wireless electronics devices. The two radiating arms of the dipole antenna are further short-circuited through a narrow shorting strip at the corners, making it possible for the antenna to be manufactured by stamping a single, flat metal plate only one time. That is, the proposed antenna in the mass-production phase can be at lower cost. In addition, by cutting an L-shaped slit at proper location in each radiating arm, a dual-band operation can easily be obtained. The design prototype of the antenna in the 2.4/5.2 GHz bands is discussed in detail in the article.
A Probe-Fed Patch Antenna with a Step-Shaped Ground Plane for 2.4 GHz Access ...Saou-Wen Su
This Letter demonstrates a new design of a probe-fed patch antenna with a modified antenna ground, and a constructed prototype ideal for applications in a 2.4-GHz WLAN access point is presented. The antenna has a thick air substrate for broadband operation and is fed by an inclined probe pin at the edge of the patch bent portion. The antenna ground comprises different portions and is in the shape of a step. With the proposed probe feed and ground configuration, good impedance bandwidth with VSWR below 1.5 over the 2.4 GHz WLAN band can be obtained. In addition, good broadside radiation characteristics have also been observed.
Matching a Bluetooth Headset Antenna on a Small System Ground by Using a Cond...Saou-Wen Su
A simple yet effective method for matching a compact planar inverted- F antenna (PIFA) on a small system circuit board for Bluetooth-headset applications is presented. The antenna is perpendicular to and extends along the top and right sides of the system ground, making it possible for the antenna to occupy almost no limited board space. Results have shown that by introducing a thin conductive wire soldered to the bottom corner of the system ground, good input matching over the 2400-2484 MHz band can easily be achieved for the PIFA mounted on a small ground of length less than a quarter wavelength at 2440 MHz. Radiation measurements of the proposed design in a real headset attached to a standard head phantom are also taken.
Wideband Rod-Dipole Antenna with a Modified Feed for DTV Signal ReceptionSaou-Wen Su
A wideband rod-dipole antenna with a modified feed for DTV signal reception in the 470-862-MHz UHF band is presented. The antenna consists of two retractable rod-dipole arms, which are connected to the opposite top corners of the modified feed. The feed is in the shape of a rectangle with dimensions 20 mm × 40 mm and divided into two portions by a U slit. The antenna can generate nearby resonant modes to attain a wide operating band, exceeding 60% bandwidth with VSWR below 3, much larger than that of the conventional center-fed dipole antenna. In addition, with the two dipole arms designed at the production stage to be able to swivel around, the antenna radiation and polarization thereof can easily be adjusted for better DTV signal reception without moving the whole antenna structure.
2005 IEEE AP-S-Compact Printed Band-Notched UWB Slot AntennaSaou-Wen Su
A compact printed ultra-wideband (UWB, 3.1 ~ 10.6 GHz) circular slot antenna having a notched frequency band at 5 GHz is presented. The antenna is a uniplanar structure and occupies a compact area of 25 x 26 mm2 only (side length less than 27% of the lower edge frequency at 3.1 GHz). The antenna has a U-slotted circular stub embedded inside the circular slot. By choosing the length of the U-slot cut in the circular stub to be about a half-wavelength of the desired notched frequency, a band-notched UWB operation is obtained.
2005 IEEE AP-S-Internal Shorted Patch Antenna for UMTS Mobile PhoneSaou-Wen Su
A novel design of feeding and short-circuiting an internal patch antenna for mobile phones is presented. The patch antenna is with a simple rectangular patch and is fed through and short-circuited to a small ground plane (denoted as antenna ground here) protruded from the main or bottom ground of a folder-type mobile phone. With the presence of the small antenna ground, which can function as a shielding wall, the proposed antenna can be placed in close proximity to the RF shielding metal box in the mobile phone, with very small effects on the antenna performances.
2007 IEEE AP-S-Internal UWB Metal-Plate Monopole Antenna for a Wireless USB D...Saou-Wen Su
A novel ultra-wideband (UWB) monopole antenna suitable to be mounted on the printed circuit board (PCB) of a wireless universal serial bus (USB) dongle as an internal antenna is presented. The proposed antenna in the study is a U-shaped metal plate monopole antenna easily fabricated from bending a simple metal plate onto a foam base of a compact size of 6 x 11 x 20 mm3. The antenna mainly comprises a pair of wide-ended radiating arms and a bevelled feeding transition. When the antenna is mounted at the top portion of the PCB, one end of the radiating arm is also short-circuited to the system ground plane. With the proposed antenna structure, which can provide a very wide operating bandwidth of larger than 7.6 GHz, the antenna’s impedance bandwidth can easily cover the 3.1–10.6 GHz UWB band.
2. Figure 2 The photo of the antenna working samples made of a 0.3-mm
thick alloy [Color figure can be viewed in the online issue, which is
available at www.interscience.wiley.com]
Figure 4 Measured 3D radiation patterns at 752 MHz for the 700 MHz
antenna studied in Figure 3 [Color figure can be viewed in the online issue,
which is available at www.interscience.wiley.com]
(width 2 mm) for lowering the operating frequency is utilized. This
patch-like monopole antenna is also operated as a quarter-wave-
length resonant structure, and in general, both the length and the 3. RESULTS AND DISCUSSION
width of the plate determine the center frequency about 2545 MHz Figures 3(a) and 3(b) show the measured and simulated reflection
of the resonant mode for 2.4-GHz WLAN/2.5-GHz WiMAX op- coefficient (S11 for the 700 MHz antenna, S22 for the WLAN/
eration. WiMAX antenna) and isolation (S21). It is first noticed that, in
general, the experimental data compare favorably with the simu-
lation results, which are based on the finite element method. The
impedance matching for frequencies across the 700-MHz band, the
2.4-GHz WLAN band, and the 2.5-GHz WiMAX band is all less
than 6 dB (3:1 VSWR) and even well below 10 dB in both the
WLAN and WiMAX bands. The isolation between the two anten-
nas remains less than about 20 and 30dB over the 700-MHz
band and the WLAN/WiMAX band, respectively. Notice that the
second resonant mode of the 700-MHz antenna is found at about
1.45 GHz. That is, the frequency ratio of the antenna upper to
lower resonant mode is close to 2, which is largely due to the
effects of the meandered structure in the 700-MHz antenna.
Figures 4– 6 give the measured radiation patterns at 752, 2442,
and 2593 MHz. The far-field 3D radiation patterns were measured
at a fully anechoic chamber (dimensions 3 3 7 m3) at Lite-On
Technology. The 3D measurement system uses the great-circle
method and is equipped with a dual-polarized horn as a receiving
(a) antenna. The radiation characteristics for the 700-MHz antenna
resemble those of the mobile-phone antenna for GSM operation, in
(b)
Figure 3 Reflection coefficients (S11 for the 700 MHz antenna, S22 for
the WLAN/WiMAX antenna) and isolation (S21) between the two anten- Figure 5 Measured 3D radiation patterns at 2442 MHz for the WLAN/
nas: (a) measured results; (b) simulated results [Color figure can be viewed WiMAX antenna studied in Figure 3. [Color figure can be viewed in the
in the online issue, which is available at www.interscience.wiley.com] online issue, which is available at www.interscience.wiley.com]
DOI 10.1002/mop MICROWAVE AND OPTICAL TECHNOLOGY LETTERS / Vol. 50, No. 11, November 2008 2949
3. is seen to be in the direction of the system ground plane ( x
direction here), which behavior shows no particular distinction
between the proposed and other small 2.4-GHz antennas for PDA
phone applications [10 –13]. Figures 7(a) and 7(b) present the
measured peak antenna gain and radiation efficiency for 700 MHz
and 2.4-GHz WLAN/2.5-GHz WiMAX operation. In the 700-
MHz band, the peak gain is in the range of 1.5–2.6 dBi with the
radiation efficiency above 64%. As for the WLAN/WiMAX bands,
Figure 6 Measured 3D radiation patterns at 2593 MHz for the WLAN/
WiMAX antenna studied in Figure 3 [Color figure can be viewed in the
online issue, which is available at www.interscience.wiley.com]
which dipole-like radiation is obtained with omnidirectional pat-
tern in the plane (the y–z plane in this study and two nulls in the
x axis direction) perpendicular to the ground plane at the longer
side [6 –9]. Also, no major difference is observed for radiation
patterns at 2442 and 2593 MHz, which suggests stable radiation
properties for the WLAN/WiMAX antenna. In addition, the max-
imum radiation over the 2.4-GHz WLAN/2.5-GHz WiMAX bands
(a)
(a)
(b) (b)
Figure 7 Measured peak antenna gain and radiation efficiency for the Figure 8 Simulated reflection coefficients (S11, S22) and isolation (S21)
two antennas studied in Figure 3: (a) for the 700 MHz antenna; (b) for the for the case with (a) a common shorting wall and (b) a CCD shielding
WLAN/WiMAX antenna [Color figure can be viewed in the online issue, cylinder [Color figure can be viewed in the online issue, which is available
which is available at www.interscience.wiley.com] at www.interscience.wiley.com]
2950 MICROWAVE AND OPTICAL TECHNOLOGY LETTERS / Vol. 50, No. 11, November 2008 DOI 10.1002/mop