Small dual C-slot printed antenna

A novel shorted dual C-slot printed antenna is presented. The antenna consists of two C-shaped slots embedded within the shorted patch antenna to maximise the current path of the antenna. A 10 dB return loss bandwidth of 5.4% has been achieved. The overall dimension of the antenna is 0.11/spl lambda//sub 0//spl times/0.074/spl lambda//sub 0//spl times/0.074/spl lambda//sub 0/ and is suitable for application where limited space is a premium. Importantly, the antenna is easy to develop.     

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.     

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.     

Integration of microstrip antenna on cavity-down ceramic ball grid array package

The integration of a microstrip antenna on a thin 17/spl times/17/spl times/2 mm cavity-down ceramic ball grid array package is reported. The antenna, intended for use in either single-chip or single-package wireless transceivers, has achieved an impedance bandwidth of 1.25% and gain of 4.6 dBi at 5.15 GHz.     

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.     

Small broadband disc-loaded monopole antenna with probe feed and folded stripline

A small broadband disc-loaded monopole antenna with a probe feed and folded stripline is presented. The antenna is composed of a rectangular disc with multiple shorting pins and a probe feed with a folded stripline that are coupled electromagnetically. The dimensions of the proposed antenna are 12/spl times/12/spl times/10 mm, and it has a measured impedance bandwidth of 700 MHz for VSWR <2 with a centre frequency at 2.54 GHz, which is approximately 27.5% of a fractional bandwidth.     

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.     

Photodiode-integrated microstrip antenna array for subterahertz radiation

The radiation characteristics of subterahertz (sub-THz) electromagnetic waves emitted from an antenna array integrated with photodiodes are investigated. The element of the fabricated array antenna was a 300-GHz microstrip antenna integrating a uni-traveling carrier photodiode. It was observed that the beamwidth of a 3 /spl times/ 1 antenna array is about half that of the single microstrip antenna. We also confirmed that the radiation direction changed by 20/spl deg/ when 2/spl pi//5 of phase difference was added to the input optical signal for each antenna element. These results demonstrated that sub-THz waves emitted by each element of the array were coherently superimposed and the power combining of the sub-THz radiation occurred in the microstrip antenna array. The measured output power of each radiation element is about 120 /spl mu/W, and a total output power of 1 mW can be estimated for a fabricated 3 /spl times/ 3 array in an ideal radiation condition.     

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.     

A compact and broadband microstrip antenna design using a geometrical-methodology-based artificial neural network

A new artificial neural-network-based methodology for a microstrip antenna design was studied and presented. The methodology is applicable to DCS, GSM, WLL, WLAN, large band planar antennas, and fractals. In this paper, we present five applications of this methodology, three of which are applicable in the WLL, 802.11a, and 802.11b antenna standards. The two others are broadband designs with 500 MHz and 1 GHZ bandwidth, respectively. All the antennas radiate an end-fire beam, and have compact sizes of 29 mm /spl times/ 25 mm, 10 mm /spl times/ 13.5 mm, 10.3 mm /spl times/ 17.2 mm, 35 mm /spl times/ 25 mm, and 35 mm /spl times/ 25 mm, respectively.     

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.     

Package-level integrated antennas based on LTCC technology

We propose a novel package topology integrating multilayer miniaturized antennas. Such a functional package is suitable for the design of a system-on-chip device, or of system-on-package applications. A stacked patch antenna is designed and integrated in a package using a low temperature co-fired ceramic process. The overall size of the package is 10.3/spl times/10.3/spl times/1.3 mm/sup 3/, and this package contains an 8.3/spl times/8.3/spl times/0.7 mm/sup 3/ internal space for the integration of chip-scale packaged components. The package is mounted on a 20/spl times/20 mm/sup 2/ ground plane to miniaturize the volume of the system. The antenna is designed to have two neighboring resonant frequencies at 5.264 and 5.355 GHz, resulting in a 140 MHz impedance bandwidth. However, the measured resonant frequencies occur at slightly higher frequencies due to manufacturing tolerances. Radiation patterns are similar to a conventional patch antenna. In addition, various parasitic effects rooted in the package size, ground size, antenna height, SMA connector, via misalignment, and the number of via holes and their locations are fully investigated.     

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.     

A new Millimeter-wave printed dipole phased array antenna using microstrip-fed coplanar stripline tee junctions

A new millimeter-wave printed twin dipole phased array antenna is developed at Ka band using a new microstrip-fed CPS tee junction, which does not require any bonding wires, air bridges, or via holes. The phased array used a piezoelectric transducer (PET) controlled tunable multitransmission line phase shifter to accomplish a progressive phase shift. A progressive phase shift of 88.8/spl deg/ is achieved with the 5 mm of perturber length when the PET has full deflection. Measured return loss of the twin dipole antenna is better than 10 dB from 29.5 to 30.35 GHz. Measured return loss of better than 15 dB is achieved from 30 to 31.5 GHz for a 1/spl times/8 phased array. The phased array antenna has a measured antenna gain of 14.4 dBi with 42/spl deg/ beam scanning and has more than 11 dB side lobe suppression across the scan.     

Reduced sidelobe four-beam antenna array fed by modified Butler matrix

A novel four-beam antenna array fed by a modified 4/spl times/8 Butler matrix is proposed. Four 180/spl deg/ directional couplers in conjunction with a 4/spl times/4 Butler matrix are applied to provide a tapered excitation of a linear eight-element switched-beam antenna array. Sidelobes as low as -20 dB for all four beams have been both theoretically and experimentally achieved. A proposed technique of antenna element rotation simplifies the design of a feeding network.     

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 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.     

A 60-GHz multilayer parasitic microstrip array antenna on LTCC substrate for system-on-package

This letter describes a compact and high-gain multilayer parasitic microstrip array antenna (MPMAA). The design and performance of the proposed array antenna are presented. The antenna employs three layers with a 2/spl times/2 parasitic array on each layer. The developed prototype MPMAA employs a multilayer low-temperature co-fired ceramic (LTCC) substrate that is well suited to the assembly of MMIC chips. The fabricated MPMAA achieves a 7.17 dBi absolute gain at 60 GHz including the loss derived from the feeding parts and RF probe to measure its antenna performance. The spacing of the top layer of the parasitic array constructed by 2/spl times/2 elements has a free-space wavelength of 0.36 and the chip size is 10 mm/sup 2/. The fabricated MPMAA achieves both compact and high directional gain and satisfies the requirements for a millimeter-wave system-on-package (SOP).     

CLIP antenna for wireless bluetooth applications

In this paper, a novel design for a coplanar waveguide antenna is developed that consists of two U-shaped slots. The antenna is named CLIP. The antenna was designed for a central frequency of 2.4 GHz, with an input impedance of 50 /spl Omega/. The antenna dimensions represent a 72% size reduction compared to a conventional microstrip rectangular-patch antenna. The measured antenna bandwidth was about 11%, while its gain was about 17 dB. These values are fairly acceptable in all wireless communication systems. The antenna configuration has a bidirectional radiation pattern, while a unidirectional radiation pattern was achieved by using a /spl lambda//sub 0//4 reflector with a metal plate. A 2/spl times/2 multi-element sub array was implemented to widen the application area. The mutual coupling between adjacent elements was low. Orthogonal-plane coupling between adjacent elements was introduced to increase the reduction in the mutual coupling. The mutual coupling level was reduced to less than -23 dB in all coupling planes. The CLIP antenna element and arrays were fabricated. Experimental measurements showed very good performance, which agreed well with simulation results.     

Land mobile-satellite MIMO capacity predictions

Satellite-MIMO, space-time coded for capacity gain, is investigated, and complementary cumulative distribution function outage and capacity predictions are provided using a verified physical-statistical MIMO land mobile-satellite channel model. Capacity results obtained for a single satellite, single antenna terminal (SISO), a dual satellite, single antenna terminal (2/spl times/1 MISO) and a dual satellite, dual antenna terminal (2/spl times/2 MIMO) system are compared, showing the benefit of satellite-MIMO.