This article presents the design and implementation of a high-gain tunable dual-band pattern reconfigurable antenna for vehicular communications. The proposed antenna consists of a slotted patch loaded with a double-side FSS acting as superstrate. The proposed slotted antenna operates at 2.45 and 3.5 GHz and the frequency tuning over the dual-band is accomplished by employing a varactor diode for tuning the center frequency from 2.41 to 2.62 GHz and from 3.38 to 3.65 GHz at lower and upper frequency bands, respectively. To obtain pattern reconfiguration, the slotted patch is divided into four regions by using two diagonal lines of vias. By properly choosing the excitation port combinations, 14 different radiation patterns are realized with a maximum realized gain of 8.4 and 7.9 dB. Further enhancement of gain is achieved using frequency-selective surface (FSS) screens which act as a partially reflecting surface. The unique feature of this design is to provide reflection coefficient with high reflectivity in two predetermined frequency ranges. The prototype antenna is fabricated and the measurement results are reported. The experimental results show that the prototype antenna with FSS offers tunable dualband with beam reconfigurable properties. K E Y W O R D Sfrequency-selective surface, multipattern antenna, pattern reconfiguration

No abstract

This article presents the design of a pattern switchable patch antenna for vehicular applications. The proposed antenna has a square patch that is divided into four triangular regions using diagonal rows of vias. The triangular regions are separately excited using a coaxial feed to achieve frequency and pattern reconfiguration. Each triangular section of the antenna has “U” shaped and inner rectangular strips to obtain two resonant frequencies of 2.4 and 3.5 GHz, respectively to cover the part of WLAN, WiMax, and car‐to‐car communication ranging from 3.4 to 3.8 GHz. In order to cover the maximum bandwidth of WLAN and WiMax standards, frequency tuning is done using a varactor diode. Upon exciting any one of the port, the antenna generates a tilted beam with a peak gain of 6.8 and 5.8 dBi at 2.45 and 3.5 GHz, respectively. A full azimuth beam coverage can be achieved by exciting the ports sequentially. The antenna is also capable of generating eight other beams using multiple feed excitations with the maximum gain of 8.4 and 9.4 dBi for the axial beam at 2.45 and 3.5 GHz, respectively.

No abstract

This article presents the design of a multipattern antenna with pattern switching for vehicular communications. The proposed antenna has four triangular patches integrated onto a split square ring (SR) resonator to operate at two distinct frequencies, viz. 2.4 and 3.5 GHz. The proposed antenna is designed with a view to enhancing the link reliability of Wireless Local Area Network (WLAN), WiMax, and vehicle to vehicle communication frequencies. Each triangular patch is separately excited using a microstrip line feed to enable beam steering. The ground plane of the antenna is embedded with two SR slots to improve the bandwidth and radiation performance. Further gain enhancement is achieved by loading the antenna with a plane reflector located at a distance of 20 mm from the antenna's ground surface. In reality, this reflector is realized using the vehicle's roof which provides gain enhancement up to 5.2 dBi at 2.4 GHz and 4 dBi at 3.5 GHz. By exciting single to multiple ports sequentially 16 different radiation patterns are obtained, which provides high‐gain omnidirectional coverage. The prototype antenna is fabricated and the simulation results are verified using experimental measurements. From the results, it is evident that the proposed antenna is suitable for vehicular communication applications.