Reflective array antenna

About: Reflective array antenna is a research topic. Over the lifetime, 4366 publications have been published within this topic receiving 57884 citations.

Modeling of slow-wave EBG structure for printed-bowtie antenna array

Abstract: The novel printed antenna array consisting of series-fed bowtie radiators, finite-width conductor-backed coplanar waveguide-to-coplanar stripline (FW-CBCPW-to-CPS) transitions, and slow-wave electromagnetic bandgap (EBG) structure is presented. By controlling the size and the cascaded number of EBG cell, this structure appears as a slow-wave transmission line that can exhibit large phase shift with broad bandwidth for antenna array applications. The equivalent circuit is also established to model the phase shift of EBG cell. Measured results show that the antenna array achieves a 50% frequency bandwidth for 10-dB return-loss criterion and an end-fire radiation pattern with a front-to-back ratio greater than 20 dB. Good agreement among measured, full-wave simulated, and calculated results supports the validity of the phase-shifting model of EBG structure to predict the main beam angle of the antenna array. Compared to the conventional solid-state phase shifters for antenna arrays, the proposed slow-wave EBG structure has the advantages of higher compactness and lower cost and it is easier to integrate in the FW-CBCPW-fed bowtie antenna array with broad-band and end-fire radiation characteristics.

Side lobe level reduction in antenna array using weighting function

Abstract: Phased array antennas are generally used for the inherent flexibility to steer the beam electronically and also the need for specialized multi-function radar systems In the antenna arrays the side lobe level is main problem which causes the wastage of energy In this paper a different windowing techniques are used to suppress the side-lobes in linear, planar and circular array antennas, by varying the various parameters like number of antenna elements, scan angle, element spacing and window coefficients The result of antenna gain pattern has been simulated by applying Kaiser, Hamming, Hann and Blackman window It is revealed that the Blackman window is better for reduction of side lobe in analyzing linear, rectangular and circular array antennas

Technical issues associated with the detection of buried land mines with high-frequency seismic waves

Abstract: An array of radars is developed as a stand off sensor for use in elastic/seismic mine detection systems. The array consists of N radar sensors which operate independently to sense the displacement of the surface of the earth due to elastic waves propagating in the earth. Each of the sensors consists of a lens-focused, conical, corrugated, horn antenna and a homodyne radar. The focused antenna allows the sensor to have greater standoff than with the previous unfocused antenna while maintaining the spatial resolution required for a mine detection system. By using an array of N sensors instead of a single sensor, the scan rate of the array is improved by a factor of N. A theoretical model for the focused antenna is developed and an array of two radars is developed and used to validate the theoretical model. This array is tested in both the experimental and the field models for the elastic mine detection system. Results from both systems are presented.© (2002) COPYRIGHT SPIE--The International Society for Optical Engineering. Downloading of the abstract is permitted for personal use only.

A comparison of switched pattern diversity antennas

Abstract: Switched pattern diversity reception is implemented by using antenna elements with different directional radiation patterns and switching the receiver to the element providing the best output. The use of pattern diversity can improve system performance. The performance of various ideal pattern diversity antennas is simulated. The results are compared with an ideal omnidirectional antenna and with energy density antennas. Significant improvements are shown for diversity antennas in multipath environments characterized by Rayleigh and Rician amplitude distributions.

Comparisons between 2D and 3D uniform array antennas

Abstract: For any wireless communications antenna system becomes indispensable. In this paper we analyzed linear array, planar array and three - dimensional (3D) array antennas. The array systems are simulated in Matlab based on uniform linear array antennas. Comparisons between planar array antenna and 3D array antenna are provided take into account different phases of currents injected in antenna elements. Also we propose to use the array antenna in WSN due to the advantages in signal to noise ratio and power consumption.