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A communication well is a well digged underground for data communication with base station using a specific antenna. To use communication wells, there is a need to design the specific antenna working at 836 MHz and 881 MHz frequency with each bandwidth of 50 MHz. The antenna should be embedded on the side of the well so that it does not take much room and the antenna should have a certain radiation direction. To meet requirements, a configurable dual-H type planar slot antenna with adjustable antenna directivity has been designed, fabricated and measured as part of out work. In this paper we studied the influence of edge structure on the antenna directivity and find out that antenna's radiation directivity is adjustable. By carefully designing the edge structure, we obtained the desired radiation pattern. All antenna parameters are optimized. Our work shows that the return loss of proposed antenna is −19 dB at 836 MHz and −15 dB at 881 MHz. The bandwidth spans from 800 MHz to 1 GHz. The measured maximum gain at each frequency is around 3 dB at a fixed direction. The measured results show that the propoesed antenna is applicable for communication wells. [ABSTRACT FROM PUBLISHER]

A low-profile dual-band three-dimensional antenna covering bands of 915 MHz and 2.45 GHz is proposed for radio frequency identification (RFID) applications. The eighth-wavelength antenna utilizes the planar triangular patches and a disk to reduce the profile. Planar tuning patches are adopted to replace the conventional tuning poles for improving the impedance matching. Silence element, defined as a radiator with little influence on others, is composed of quarter-wavelength patch working at higher band in this study. The antenna with a merit of good production consistency exhibits an impedance bandwidth of 22% from 842 to 1049 MHz in the lower band, while the upper band covers 100 MHz (from 2.4 to 2.5 GHz). The measured peak gain is 3dBi and 5dBi at 915 MHz and 2.45 GHz, respectively. [ABSTRACT FROM PUBLISHER]

A novel planar Coaxial Collinear (COCO) antenna with rectangular coaxial strip is presented. The planar COCO antenna is fed by microstrip and comprises several radiation sections of rectangular coaxial strips which are cross-linked one by one. A prototype has been designed and fabricated to cover the band of 2.4–2.48 GHz. The simulated and measured results show that the fractional −10 dB bandwidth of the prototype is 24.5%. With this band, the prototype possesses an omni-directional radiation pattern and achieves a gain of over 4 dBi in the direction of θ = 50°. The proposed antenna has characteristics of planar shape, compact size, wideband and easy fabrication. It is suitable for base station application of WiFi, RFID et al. [ABSTRACT FROM PUBLISHER]

In this paper, a three-layered slot antenna with compact size and high gain is proposed at 5.4 GHz for Wi-MAX (5.2∼5.8 GHz) applications. Simulated gain of 12dBi and measured gain of 10.48dBi are achieved and the impedance bandwidth is 22.59%. The efficiency is measured of 97.23%. Measured and simulated results are in good agreement. The overall size of the antenna is 100×100 ×21.5 mm3. [ABSTRACT FROM PUBLISHER]

A coplanar waveguide fed (CPW-Fed) monopole antenna with dual band-notched characteristics is presented in this paper. The design and simulation of the antenna is completed by High Frequency Structure Simulator (HFSS) software. HFSS is a frequency-domain simulation software based on Finite Element Method (FEM). With the help of this software, the proposed antenna has very good performance. It consists of stepped rectangle patch, stepped ground planes and stepped feed lines. These steps improve the input impedance bandwidth and radiation characteristics. By removing a U-shaped slot and C-shaped one from the stepped patch, band rejected property in the 3.5GHz/5.5GHz band is obtained. Moreover, the two bands can be adjusted independently. The compact antenna has the promising performance including broadband impedance matching, consistent radiation pattern and stable gain. [ABSTRACT FROM PUBLISHER]

The design is described of a dual-band antenna which is applied by high-speed train. This antenna is comprised of an alloy base, a cover and an FR4 substrate carved with two printed antennas on it. The antenna is designed to achieve dual-band operation in the 457MHz∼469MHz and 820MHz∼935MHz with a simple configuration. The simulated and measured results of the antenna, such as magnitude of the reflection coefficient (S11), gain, and radiation patterns are all presented in this paper. [ABSTRACT FROM PUBLISHER]