Showing papers on "Dipole antenna published in 2008"

Nanometre-scale germanium photodetector enhanced by a near-infrared dipole antenna

Abstract: A critical challenge for the convergence of optics and electronics is that the micrometre scale of optics is significantly larger than the nanometre scale of modern electronic devices. In the conversion from photons to electrons by photodetectors, this size incompatibility often leads to substantial penalties in power dissipation, area, latency and noise1,2,3,4. A photodetector can be made smaller by using a subwavelength active region; however, this can result in very low responsivity because of the diffraction limit of the light. Here we exploit the idea of a half-wave Hertz dipole antenna (length ∼ 380 nm) from radio waves, but at near-infrared wavelengths (length ∼ 1.3 µm), to concentrate radiation into a nanometre-scale germanium photodetector. This gives a polarization contrast of a factor of 20 in the resulting photocurrent in the subwavelength germanium element, which has an active volume of 0.00072 µm3, a size that is two orders of magnitude smaller than previously demonstrated detectors at such wavelengths. By scaling down device size, the principles of radio antennas can be used in the optical regime. These optical antennas act as a bridge between optics and electronics, collecting and enhancing light to enable the creation of tiny semiconductor photodetectors.

Engineering the optical response of plasmonic nanoantennas

Abstract: The optical properties of plasmonic dipole and bowtie nanoantennas are investigated in detail using the Green’s tensor technique. The influence of the geometrical parameters (antenna length, gap dimension and bow angle) on the antenna field enhancement and spectral response is discussed. Dipole and bowtie antennas confine the field in a volume well below the diffraction limit, defined by the gap dimensions. The dipole antenna produces a stronger field enhancement than the bowtie antenna for all investigated antenna geometries. This enhancement can reach three orders of magnitude for the smallest examined gap. Whereas the dipole antenna is monomode in the considered spectral range, the bowtie antenna exhibits multiple resonances. Furthermore, the sensitivity of the antennas to index changes of the environment and of the substrate is investigated in detail for biosensing applications; the bowtie antennas show slightly higher sensitivity than the dipole antenna.

A Compact Ultrawideband Antenna With 3.4/5.5 GHz Dual Band-Notched Characteristics

Abstract: We propose a compact planar ultrawideband (UWB) antenna with 3.4/5.5 GHz dual band-notched characteristics. The antenna consists of a beveled rectangular metal patch and a 50 Omega coplanar waveguide (CPW) transmission line. By etching two nested C-shaped slots in the patch, band-rejected filtering properties in the WiMAX/WLAN bands are achieved. The proposed antenna is successfully simulated, designed, and measured showing broadband matched impedance, stable radiation patterns and constant gain. An equivalent circuit model of the proposed antenna is presented to discuss the mechanism of the dual band-notched UWB antenna. A UWB antenna and a single band-notched one are also provided for references.

Isolation Enhancement Between Two Closely Packed Antennas

Abstract: This paper introduces a coupling element to enhance the isolation between two closely packed antennas operating at the same frequency band. The proposed structure consists of two antenna elements and a coupling element which is located in between the two antenna elements. The idea is to use field cancellation to enhance isolation by putting a coupling element which artificially creates an additional coupling path between the antenna elements. To validate the idea, a design for a USB dongle MIMO antenna for the 2.4 GHz WLAN band is presented. In this design, the antenna elements are etched on a compact low-cost FR4 PCB board with dimensions of 20times40times1.6 mm3. According to our measurement results, we can achieve more than 30 dB isolation between the antenna elements even though the two parallel individual planar inverted F antenna (PIFA) in the design share a solid ground plane with inter-antenna spacing (Center to Center) of less than 0.095 lambdao or edge to edge separations of just 3.6 mm (0.0294 lambdao). Both simulation and measurement results are used to confirm the antenna isolation and performance. The method can also be applied to different types of antennas such as non-planar antennas. Parametric studies and current distribution for the design are also included to show how to tune the structure and control the isolation.

Design and Evaluation of a Reconfigurable Antenna Array for MIMO Systems

Abstract: New reconfigurable antenna array is demonstrated for multiple input multiple output (MIMO) communication systems that improves link capacity in closely spaced antenna arrays. The antenna system consists of an array of two printed dipoles separated by a distance of a quarter wavelength. Each of the dipoles can be reconfigured in length using PIN diode switches. The switch configuration can be modified in a manner adaptive to changes in the environment. The configuration of switches effects the mutual coupling between the array elements, and subsequently, the radiation pattern of each antenna, leading to different degrees of pattern diversity which can be used to improve link capacity. The PIN diode-based reconfigurable antenna solution is first motivated through a capacity analysis of the antenna in a clustered MIMO channel model. A new definition of spatial correlation coefficient is introduced to include the effects of antenna mismatch and radiation efficiency when quantifying the benefit of pattern diversity. Next, the widespread applicability of the proposed technique is demonstrated, relative to conventional half wavelength printed dipoles, using computational electromagnetic simulation in an outdoor and indoor environment and field measurements in an indoor laboratory environment. It is shown for the 2 times 2 system considered in this paper, that an average improvement of 10% and 8% is achieved in link capacity for a signal to noise ratio (SNR) respectively of 10 dB and 20 dB in an indoor environment compared to a system employing non reconfigurable antenna arrays.

Multimode antenna structure

Abstract: One or more embodiments are directed to a multimode antenna structure for transmitting and receiving electromagnetic signals in a communications device. The communications device includes circuitry for processing signals communicated to and from the antenna structure. The antenna structure is configured for optimal operation in a given frequency range. The antenna structure includes a plurality of antenna ports operatively coupled to the circuitry, and a plurality of antenna elements, each operatively coupled to a different one of the antenna ports. Each of the plurality of antenna elements is configured to have an electrical length selected to provide optimal operation within the given frequency range. The antenna structure also includes one or more connecting elements electrically connecting the antenna elements such that electrical currents on one antenna element flow to a connected neighboring antenna element and generally bypass the antenna port coupled to the neighboring antenna element. The electrical currents flowing through the one antenna element and the neighboring antenna element are generally equal in magnitude, such that an antenna mode excited by one antenna port is generally electrically isolated from a mode excited by another antenna port at a given desired signal frequency range without the use of a decoupling network connected to the antenna ports, and the antenna structure generates diverse antenna patterns.

Compact diversity antenna system

Abstract: The present invention provides a compact antenna system having multiple antennas exhibiting polarization and pattern diversity. The system comprises at least two antennas which may have different polarizations, operatively coupled to a passive element which operates as a Balun for a first antenna and which is configured to absorb and re-radiate electromagnetic radiation from the second antenna to produce a desired radiation pattern. The present invention also provides for additional antennas operatively coupled to the passive element or to the first antenna to provide additional diversity.

Design of compact vivaldi antenna arrays for uwb see through wall applications

Abstract: Two different types of Vivaldi antenna arrays have been designed for UWB see through wall applications. The first is a 16 × 1 antipodal Vivaldi antenna covering 8-12 GHz, and the second is an 8×1 tapered slot antenna for 2-4 GHz frequency range. The array elements are optimized to have a compact size and almost constant gain with frequency. Wilkinson power dividers were designed and fabricated to compose the feed network for the Vivaldi antenna arrays. Measured results of the manufactured antipodal and tapered slot Vivaldi antenna arrays are in excellent agreement with the simulated ones, with a gain of more than 13dBi and 12 dBi respectively within their respective operating band. The first array is geared towards see through dry wall with high resolution, while the second is designed at lower frequencies to allow see through concrete wall applications. Full arrays were manufactured and connected to multi-throw switches and have been utilized as part of synthetic aperture radar.

Transmitter Architectures Based on Near-Field Direct Antenna Modulation

Abstract: A near-field direct antenna modulation (NFDAM) technique is introduced, where the radiated far-field signal is modulated by time-varying changes in the antenna near-field electromagnetic (EM) boundary conditions. This enables the transmitter to send data in a direction-dependent fashion producing a secure communication link. Near-field direct antenna modulation (NFDAM) can be performed by using either switches or varactors. Two fully-integrated proof-of-concept NFDAM transmitters operating at 60 GHz using switches and varactors are demonstrated in silicon proving the feasibility of this approach.

A Low-Cost 60-GHz Switched-Beam Patch Antenna Array With Butler Matrix Network

Abstract: In this letter, a low-cost 60-GHz switched-beam patch antenna array with Butler matrix network is developed and experimentally demonstrated. In order to improve integration with the patch elements, a 4 times 4 planar Butler matrix is implemented in a low-dielectric substrate. The four rectangular patches fed by inset microstrip lines are connected to the outputs of the Butler matrix for the 60-GHz operation. Because of the fabrication tolerances, the operating frequency of the fabricated antenna shifts to 62 GHz. The radiation patterns measured at 62 GHz are in good agreement with the theoretical array factors. The antenna developed in this letter provides a cost-effective approach to implement an adaptive antenna for 60-GHz wireless communications.

Selectable beam antenna

Abstract: A selectable beam antenna of generally linear, polygonal, planar or polyhedral form, able to operate at microwave and millimetre wave frequencies, and constructed from associated networks that incorporate radio frequency switches, time delays and amplitude weights positioned within a set of interleaved transmission, lines or waveguides to simultaneously perform both beam-forming and beam selection operations, which selectable beam antenna comprises: (i) a single RP antenna port connected to a 1-to-N corporate feed means, where N is greater than or equal to 2; (ii) a EF switch network means of N/q multi-pole-multi-throw radio frequency switch means (qPMT) connected to the corporate feed means; (iii) a RF distribution means of N×M singularly or multiply interleaved lines arranged so as to have approximately equal transmission length connected to the switch means, where M is the number of throws associated with each radio frequency switch means (qPMT); (iv) an antenna launch means of M×M interleaved antenna element sub-groups of S linear or planar elements, where S is greater than or equal to one, σorporately connected to the distribution means and arranged to closely follow at sub-wavelength intervals a closed are or segment of a closed surface; and (v) an overall electronic control means to set all radio frequency switches in such a way to select, to time delay and to amplitude weight the activated interleaved antenna launch elements and thus generate one of the possible directed, antenna beams.

A 60-GHz Millimeter-Wave CPW-Fed Yagi Antenna Fabricated by Using 0.18- $\mu\hbox{m}$ CMOS Technology

Abstract: This letter presents a 60-GHz millimeter-wave on-chip Yagi antenna fabricated with a 0.18-mum CMOS process. A feeding network is designed in a coplanar waveguide (CPW) technology. The 0.18-mum six-metal-layer CMOS process allows the on-chip antenna to utilize a simple CPW-to-coplanar-stripline feed transition and the first metal layer to implement a reflector strip. The CMOS antenna chip size is 1.1 x 0.95 mm2 . A FEM-based 3D full-wave electromagnetic solver, the HFSS, is used for design simulation. The measured antenna input VSWR is less than two from 55 to 65 GHz. The front-to-back ratio of the Yagi antenna is about 9 dB. The measured maximum antenna power gain is about -10 dBi. The simulated antenna radiation efficiency is about 10%.

Integrated millimeter wave antenna and transceiver on a substrate

Abstract: A semiconductor chip integrating a transceiver, an antenna, and a receiver is provided. The transceiver is located on a front side of a semiconductor substrate. A through substrate via provides electrical connection between the transceiver and the receiver located on a backside of the semiconductor substrate. The antenna connected to the transceiver is located in a dielectric layer located on the front side of the substrate. The separation between the reflector plate and the antenna is about the quarter wavelength of millimeter waves, which enhances radiation efficiency of the antenna. An array of through substrate dielectric vias may be employed to reduce the effective dielectric constant of the material between the antenna and the reflector plate, thereby reducing the wavelength of the millimeter wave and enhance the radiation efficiency. A design structure for designing, manufacturing, or testing a design for such a semiconductor chip is also provided.

A Reconfigurable High-Gain Partially Reflecting Surface Antenna

Abstract: A high-gain partially reflective surface (PRS) antenna with a reconfigurable operating frequency is presented. The operating frequency is electronically tuned by incorporating an array of phase agile reflection cells on a thin substrate above the ground plane of the resonator antenna, where the reflection phase of each cell is controlled by the bias voltage applied to a pair of varactor diodes. The new configuration enables continuous tuning of the antenna from 5.2 GHz to 5.95 GHz using commercially available varactor diodes, thus covering frequencies typically used for WLAN applications. Both the PRS and phase agile cell are analyzed, and theoretical and measured results for gain, tuning range, and radiation patterns of the reconfigurable antenna are described. The effect of the varactor diode series resistance on the performance of the antenna is also reported.

Dual staggered vertically polarized variable azimuth beamwidth antenna for wireless network

Abstract: An antenna system for wireless networks having a dual stagger antenna array architecture is disclosed. The antenna array contains a number of driven radiator elements that are spatially arranged in two vertically aligned groups each having pivoting actuators so as to provide a controlled variation of the antenna array's azimuth radiation pattern.

Partitioned aperture array antenna

Abstract: A partitioned aperture array antenna. The novel antenna includes a first subarray having a first number of antenna elements equipped with transmit functionality and a second subarray having a second number of antenna elements equipped with receive functionality, wherein the first and second numbers are not equal and the first and second subarrays have at least one common antenna element. In an illustrative embodiment, the first subarray includes a transmit circuit coupled to each antenna element in the first subarray for controlling a relative transmit phase of the antenna element to steer an overall antenna transmit beam, and the second subarray includes a receive circuit coupled to each antenna element in the second subarray for controlling a relative receive phase of the antenna element to steer an overall antenna receive beam.

CPW-Fed Koch Fractal Slot Antenna for WLAN/WiMAX Applications

Abstract: A dual wide-band CPW-fed modified Koch fractal printed slot antenna, suitable for WLAN and WiMAX operations, is proposed in this paper. Here, the operating frequency of a triangular slot antenna is lowered by the Koch iteration technique resulting in a compact antenna. Studies on the impedance and radiation characteristics of the proposed antenna indicate that a modified Koch fractal slot antenna has an impedance bandwidth from 2.38 to 3.95 GHz and 4.95-6.05 GHz covering 2.4/5.2/5.8 GHz WLAN bands and the 2.5/3.5/5.5 GHz WiMAX bands. The antenna exhibits omnidirectional radiation coverage with a gain better than 2.0 dBi in the entire operating band. Empirical relations are deduced and compared with the results.

A Compact Multiband Monopole Antenna With a Defected Ground Plane

Abstract: A compact multiband antenna is proposed that consists of a printed circular disc monopole antenna with an L-shaped slot cut out of the ground, forming a defected ground plane. Analysis of the current distribution on the antenna reveals that at low frequencies the addition of the slot creates two orthogonal current paths, which are responsible for two additional resonances in the response of the antenna. By virtue of the orthogonality of these modes the antenna exhibits orthogonal pattern diversity, while enabling the adjacent resonances to be merged, forming a wideband low-frequency response and maintaining the inherent wideband high-frequency response of the monopole. The antenna exhibits a measured -10 dB S 11 bandwidth of 600 MHz from 2.68 to 3.28 GHz, and a bandwidth of 4.84 GHz from 4.74 to 9.58 GHz, while the total size of the antenna is only 24 times 28.3 mm. The efficiency is measured using a modified Wheeler cap method and is verified using the gain comparison method to be approximately 90% at both 2.7 and 5.5 GHz.

A Printed Monopole Antenna With Two Steps and a Circular Slot for UWB Applications

Abstract: This letter presents a printed monopole antenna with two steps and a circular slot for ultrawide band (UWB) applications. The proposed antenna is fabricated and tested. The proposed antenna has a wide frequency bandwidth of 8.4 GHz starting from 3 GHz up to 11.4 GHz for a return loss (S_11) of less than - 10dB and gain flatness over the frequency range. Measured results show also that the proposed antenna features satisfactory radiation characteristics within the achieved impedance bandwidth. By introducing a simple and proper narrow slot in the radiating element, frequency-notched characteristics can be obtained and a good band-notched performance in the 56 GHz band can be achieved.

Dual band antenna and methods for use therewith

Abstract: A dual band antenna includes a far field antenna structure for facilitating the communication of first data with a remote device via far field signaling in a millimeter wave band. A near field antenna structure facilitates the communication of second data with a remote device via near field signaling in a near field band. The far field antenna structure and the near field antenna structure share at least one common antenna element.

A Printed Log-Periodic Koch-Dipole Array (LPKDA)

Abstract: Koch-shaped dipoles are introduced for the first time in a wideband antenna design and evolve the traditional Euclidean log-periodic dipole array into the log-periodic Koch-dipole array (LPKDA). Antenna size can be reduced while maintaining its overall performance characteristics. Observations and characteristics of both antennas are discussed. Advantages and disadvantages of the proposed LPKDA are validated through a fabricated proof-of-concept prototype that exhibited approximately 12% size reduction with minimal degradation in the impedance and pattern bandwidths. This is the first application of Koch prefractal elements in a miniaturized wideband antenna design.

3.5/5.5 Ghz dual band-notch ultra-wideband antenna

Abstract: A compact and simple design of a CPW-fed planar antenna for ultra- wideband application with dual band-notch characteristics is presented. The proposed antenna yields an impedance bandwidth of 3.1- 10.6 GHz with VSWR < 2, except the bandwidths of 3.3-3.9 GHz for WiMAX and 5-6 GHz for WLAN. The antenna is successfully simulated, designed, and measured, showing broadband matched impedance, stable gain and omnidirectional radiation patterns.

A Folded-Monopole Model for Electrically Small NRI-TL Metamaterial Antennas

Abstract: An improved model for analyzing electrically small NRI-TL antennas is proposed, that highlights the methods that enable these antennas to offer a good impedance match and a high radiation efficiency compared to previously reported designs. An even-odd mode analysis reveals that the antenna supports a predominately even-mode current on the vertical vias, allowing the antenna to be modeled using a multiple folded monopole topology, which provides a substantial increase in the radiation resistance of the antenna. This, together with the top-loading effect of the microstrip line on the vias, enables the antenna to be matched to 50 Omega without the use of an external matching network, while maintaining a high radiation efficiency. The validity of the proposed model is confirmed with a fabricated prototype, that consists of four microstrip zero-degree NRI-TL unit cells with dimensions of lambda0/10 times lambda0/10 times lambda/20 over a 0.45lambda0 times 0.45lambda0 ground plane. The antenna's performance is verified by full-wave simulations and experimental data obtained at 3.1 GHz, which yield a vertical linear electric field polarization, a measured -10dB return-loss bandwidth of 53 MHz and a measured efficiency of 70%.

Compact Dual-Band Slot Antenna for 2.4/5ghz WLAN Applications

Abstract: This paper presents a compact dual-band slot antenna for 2.4/5 GHz WLAN applications. The radiating elements of the proposed antenna are composed of a square ring slot and a circular ring slot, operating at 2.4 GHz and 5 GHz bands respectively. The antenna size is very compact (40 mm × 40 mm × 1 mm), and can be integrated easily with other RF front-end circuits. It is demonstrated that the proposed antenna can completely cover the required bandwidths of IEEE 802.11b/g (2.4–2.485 GHz) and IEEE 802.11a (5.15–5.825 GHz) with satisfactory radiation characteristics. Good agreement is achieved between the simulated and measured results.

A Novel Series-Fed Taper Antenna Array Design

Abstract: To improve the performance of microstrip antenna array, a matching-in-step (MIS) configuration of microstrip series-fed taper array is designed. Compared to the traditional one, the novel antenna array has a better VSWR characteristic. The design procedure of the MIS antenna array is discussed in detail, and some valuable results are acquired. Numerical results are obtained and a very good agreement is observed between experimental and simulated results of such arrays.

Printed Wide-Slot Antenna for Wideband Applications

Abstract: The design and analysis of a novel printed wide-slot antenna, fed by a microstrip line, for wideband communication systems is presented. Detailed simulation and experimental investigations are conducted to understand its behavior and optimize for broadband operation. The designed antenna has a wide operating bandwidth of over 120% (2.8-11.4 GHz) for S11 <-10 dB. In addition to being small in size, the antenna exhibits stable far-field radiation characteristics in the entire operating bandwidth, relatively high gain, and low cross polarization. By properly choosing the suitable slot shape, selecting similar feed shape and tuning their dimensions, the design with very wide operating bandwidth, relatively small size and improved radiation pattern is obtained. A comprehensive parametric study has been carried out to understand the effects of various dimensional parameters and to optimize the performance of the designed antenna. Results show that the impedance matching of this kind of antenna is greatly affected by the feed-slot combination and feed gap width, with the slot shape being a main contributor of the radiation characteristics. The simulated and measured Results for return loss, far-field E and H-plane radiation patterns, and gain of designed antenna are presented and discussed.

High-Efficiency Angled-Dipole Antennas for Millimeter-Wave Phased Array Applications

Abstract: A high-efficiency microstrip-fed endfire angled-dipole antenna has been developed for millimeter-wave phased array applications. The antenna is built on both sides of a Teflon substrate (epsivr = 2.2) and this allows a wideband feed from the single-ended microstrip line to the differential dipole. The design results in wide radiation patterns for scanning purposes with a gain of around 2.5 dB at 20-26 GHz and a cross-polarization level of 6 dB at 23.2-24.6 GHz and very low mutual coupling between elements ( 93% when referenced to the microstrip line feed (including mismatch loss). The usefulness of these antennas as phased array radiators is demonstrated by several eight-element linear arrays at 22-24 GHz with scan angle up to 50 degrees. The application areas are in automotive radars and high data-rate communication systems.

Direct Antenna Modulation (DAM) for On-Chip mm-Wave Transceivers

Abstract: In the last few decades the puissant desire to miniaturize the digital circuits to achieve higher speed and larger density has shaped the evolution of the silicon-based technologies. This development opens a new era in the field of millimeter-wave electronics in which many low-cost high-yield silicon-based transistors can be used on a single chip to enable creation of novel architectures with unique properties not achievable with old processes. In addition to this high level of integration capability, the die size of comparable or even larger than the wave-length makes it possible to integrate antennas, transceivers, and digital circuitry all on a single silicon die. It is important to realize that although smaller parasitic capacitors and shorter transistor channels have improved fT and fmax of transistors, extremely thin metal layers, highly doped substrates, and low breakdown voltage transistors have severely affected the performance of analog and RF building blocks. For example, thin metal layers have increased the loss and lowered the quality factor of the building blocks such as capacitors and inductors and low breakdown voltage transistors have made the power generation quite challenging. Additionally, if not carefully designed, small wave-lengths in the millimeter-wave range may cause unintended radiation by on-chip components. In this dissertation, we address these issues in design of millimeter-wave silicon-based single-chip phased-array transceivers with integrated antennas. We also introduce the technique of Direct Antenna Modulation (DAM) and implement two proof-of-concept chips operating at 60 GHz. We will present the receiver and the on-chip antenna sections of a fully integrated 77 GHz four-element phased-array transceiver with on-chip antennas in silicon. The receiver section of the chip includes the complete down-conversion path comprising low-noise amplifier (LNA), frequency synthesizer, phase rotators, combining amplifiers, and on-chip dipole antennas. The signal combining is performed using a novel distributed active combining amplifier at an IF of 26 GHz. In the LO path, the output of the 52 GHz VCO is routed to different elements and can be phase shifted locally by the phase rotators. A silicon lens on the backside is used to reduce the loss due to the surface-wave power of the silicon substrate. Our measurements show a single-element LNA gain of 23 dB and a noise figure of 6.0 dB. Each of the four receive paths has a gain of 37 dB and a noise figure of 8.0 dB. Each on-chip antenna has a gain of +8 dBi. A direct antenna modulation (DAM) technique is also introduced, where the radiated far-field signal is modulated by time-varying changes in the antenna near-field electromagnetic (EM) boundary conditions. This enables the transmitter to send data in a direction-dependent fashion producing a secure communication link. The transmitter architecture makes it possible to use narrow-band highly-efficient switching power amplifiers to transmit wideband constant and non-constant envelope modulated signals. Theoretically, these systems are capable of transmitting independent data in multiple directions at full-rate concurrently using a single transmitter. Direct antenna modulation (DAM) can be performed by using either switches or varactors. Two proof-of-concept DAM transmitters operating at 60GHz using switches and varactors are demonstrated in silicon proving the feasibility of this approach.

Substrate integrated waveguide antenna array

Abstract: A substrate integrated waveguide (SIW) slot full-array antenna fabricated employing printed circuit board technology. The SIW slot full-array antenna using either single or multi-layer structures greatly reduces the overall height and physical steering requirements of a mobile antenna when compared to a conventional metallic waveguide slot array antenna. The SIW slot full-array antenna is fabricated using a low-loss dielectric substrate with top and bottom metal plating. An array of radiating cross-slots is etched in to the top plating to produce circular polarization at a selected tilt-angle. Lines of spaced-apart, metal-lined vias form the sidewalls of the waveguides and feeding network. In multi-layer structures, the adjoining layers are coupled by transverse slots at the interface of the two layers.

Wideband Shorted Bowtie Patch Antenna With Electric Dipole

Abstract: A wideband directional antenna composed of a shorted bowtie patch antenna and an electric dipole is presented. Through this composition, an equivalent magnetic dipole due to the shorted bowtie patch antenna and an electric dipole are excited together. Almost equal radiation pattern in the E- and H-planes is obtained. The proposed antenna has a wide impedance bandwidth, which is over 60% for SWR. < 2 ranging from 2.16-4.13 GHz.