소형 안테나 ( Small Antennas )

In order to achieve a wide bandwidth characteristic of high gain and high efficiency antennas, a double-layer hollow-waveguide slot array is proposed, where a full-corporate-feed waveguide is arranged in the lower layer. This antenna can be built up easily by the process of diffusion bonding of laminated thin metal etching plates, which has high precision and is possibly a low cost technique. The radiating elements and the feed waveguide are designed to suppress the reflection over a wideband. The predicted bandwidth of the reflection less than -14 dB is 8.3% for a 16 × 16-element array antenna. A test antenna is fabricated in the 60-GHz band, and about 80% antenna efficiency with more than 32 dBi is achieved over 4.8 GHz.

Double-Layer Full-Corporate-Feed Hollow-Waveguide Slot Array Antenna in the 60-GHz Band

This invention is in the field of base station antennas for wireless communications. The present invention refers to a slim multi-band antenna array for cellular base stations, which provides a reduced width of the base station antenna and minimizes the environmental and visual impact of a network of cellular base station antennas, in particular in mobile telephony and wireless service networks. A multiband antenna array comprises a first set of radiating elements operating at a first frequency band and a second set of radiating elements operating at a second frequency band, said radiating elements being smaller than λ/2 or smaller than λ/3, being (λ) the longest operating wavelength. The ratio between the largest and the smaller of said frequency bands is smaller than 2.

Slim Multi-Band Antenna Array For Cellular Base Stations

The constant evolution of wireless handheld devices together with the apparition of multiple wireless communication systems fosters the antenna community to design new radiating and measurements systems capable of satisfying the market demands. It is an object of the present paper to provide an overview of the evolution that wireless handheld technology has experienced in the last years. In this sense, a description of the evolution of wireless handheld devices, regulations, challenges in today’s smartphones, and handset characterization is reviewed. Finally, recent advances in antenna technology for wireless handheld or portable devices are presented.

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Advances in Antenna Technology for Wireless Handheld Devices

A wideband 2x2-slot element for a 60-GHz antenna array is designed by making use of two double-sided printed circuit boards (PCBs). The upper PCB contains the four radiating cavity-backed slots, where the cavity is formed in substrate-integrated waveguide (SIW) using metalized via holes. The SIW cavity is excited by a coupling slot. The excitation slot is fed by a microstrip-ridge gap waveguide formed in the air gap between the upper and lower PCBs. The lower PCB contains the microstrip line, being short-circuited to the ground plane of the lower PCB with via holes, and with additional metalized via holes alongside the microstrip line to form a stopband for parallel-platemodes in the air gap. The designed element can be used in large arrays with distribution networks realized in such microstrip-ridge gap waveguide technology. Therefore, the present paper describes a generic study in an infinite array environment, and performance is measured in terms of the active reflection coefficient S11 and the power lost in grating lobes. The study shows that the radiation characteristics of the array antenna is considerably improved by using a soft surface EBG-type SIW corrugation between each 2x2-slot element in E-plane to reduce the mutual coupling. The study is verified by measurements on a 4x4 element array surrounded by dummy elements and including a transition to rectangular waveguide WR15.

/pdf/2-times-2-slot-element-for-60-ghz-planar-array-antenna-cvrhfvixky.pdf

2 $\times$ 2-Slot Element for 60-GHz Planar Array Antenna Realized on Two Doubled-Sided PCBs Using SIW Cavity and EBG-Type Soft Surface fed by Microstrip-Ridge Gap Waveguide

Excellent efficiency of a linearly polarized microstrip array in Ku-band is achieved by having proper impedance matching throughout the array and by properly using the corporate and series fed by microstrip transmission lines. The cavity-backed microstrip patch is used to obtain relatively wide bandwidth. The auto-tracking Ku-band antenna in the azimuth direction has developed with a very low profile for vehicle's rooftop mounting, as well as, a low manufacturing cost. The main beam of array is tilted 15/spl deg/ away from the broadside direction to provide optimum coverage for Korea satellite III.

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Ku-band high efficiency antenna with corporate-series-fed microstrip array

A cavity-backed slot array antenna using a single waveguide fed sub-array is presented. A subarray consists of 2/spl times/4 slot elements backed by a single cavity. By proper choice of dimensions it is shown that the proposed antenna has characteristics of high radiation efficiency and broad frequency bandwidth. Antenna characteristics for the array antenna with 256 elements are measured in Ku-band.

Cavity-backed planar slot array antenna with a single waveguide-fed sub-array

This invention relates to a microstrip array antenna, especially a broad-band dual-polarized microstrip array antenna having parallel feeding structure whose consist of two parts power supplying layers each of which generates its own polarization respectively. And the broad-band dual-polarized microstrip array antenna according to the present invention arranges transmission paths for two separate linear polarization on a different layer each other in order to minimize an interference effect and a proximity feeding method and an aperture coupled method are used in order to get two separate polarization.

Broadband dual-polarized microstrip array antenna

A linearly polarized microstrip antenna array in the Ku-band achieves high efficiency by having the proper impedance matching throughout the array and by properly using the corporate and series feeds with microstrip transmission lines. The efficiency of the antenna array is 83.3%. The cavity-backed microstrip patch is used as the element of the antenna array to obtain relatively wide bandwidth. The auto-tracking antenna in the azimuth direction is developed with a very low profile as well as a low manufacturing cost for the vehicle's rooftop mounting. The main beam of array is tilted 15° away from the broadside direction to provide optimum coverage for Korea satellite III. The measured gain of an antenna array is 23.8 dBi at the center frequency of 12.5 GHz. © 2004 Wiley Periodicals, Inc. Microwave Opt Technol Lett 43: 181–183, 2004; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/mop.20413

Broadband high-efficiency microstrip antenna array with corporate-series-feed

In this paper, a triple-band internal antenna for mobile handsets is present. Dual band operation is generated by using a band reject filter as a matching circuit and without any transformations on its radiator. Moreover, the antenna gives a wide impedance bandwidth in high band by using an additional chip capacitor so that the antenna can operate in triple-band with only one radiator. Details of the proposed antenna are presented.

/pdf/triple-band-internal-antenna-using-matching-circuits-112nuxm2qt.pdf

Gi-Cho Kang

Papers

Ku-band high efficiency antenna with corporate-series-fed microstrip array

Cavity-backed planar slot array antenna with a single waveguide-fed sub-array

Broadband dual-polarized microstrip array antenna

Broadband high-efficiency microstrip antenna array with corporate-series-feed

Triple band internal antenna using matching circuits