A Beam Switching Quasi-Yagi Dipole Antenna

Abstract

A high gain beam switching pattern reconfigurable quasi-Yagi dipole antenna is presented for wireless local area network (WLAN) systems at 5.2 GHz. The antenna consists of a microstrip-to-coplanar stripline (CPS) balun, the length of which can be controlled by using PIN diodes. The change of the length of the balun allows the currents on the two arms of the dipole to have different phase differences, thereby making the antenna operate at three states with the E-plane maximum beam direction towards 20⁰ ⁰ ⁰ ⁰, ----20⁰ ⁰ ⁰ ⁰, and 0⁰ ⁰ ⁰ ⁰, respectively. In order to validate the design method, a prototype of the proposed antenna with a practical biasing network was fabricated and measured. Measured results on the reflection coefficients, radiation patterns, and realized gains for three operating states are provided, which agree well with the numerical simulations.Index Terms-Beam switching, pattern reconfigurable antennas, microstrip antennas, quasi-Yagi antennas, dipole antennas.

Superstrate-integrated Switchable Beam Rectangular Microstrip Antenna for Gain Enhancement

“…A PIN diode was also utilized to manipulate the radiation pattern. In [6], the authors proposed a single-fed switchable beam antenna using the quasi-Yagi structure and a PIN diode to select an antenna director. Meanwhile, further improvements were made to the switchable beam antenna for the dualband operation (2.4 GHz and 5.8 GHz) [7] using frequency selective surfaces [8].…”

A Wideband Reconfigurable Antenna With 360° Beam Steering for 802.11ac WLAN Applications

“…As shown in Figs. 8(c) and (d), the ONand OFF-status of a PIN diode can be represented by the equivalent circuit models as a series-connected RL circuit and a parallel-connected RC circuit, respectively, where the components values are R on = 4 Ω, L on = 0.4 nH, R off = 20 kΩ and C off = 0.04 pF [28].…”

“…This kind of antennas are usually driven by one or more radiating elements and directed by several parasitic elements at certain directions. By controlling the ON and OFF status of the switches, the parasitic elements function as directive and reflective unit forming a directional beam at certain angle [9], [13], [14], [28]. However, the reported patch antennas with parasitic elements suffer from narrow bandwidths and limited gain.…”

A Reconfigurable Partially Reflective Surface (PRS) Antenna for Beam Steering

“…Although phased array antennas are capable of providing a wide beam steering angle, they have the drawbacks of high costs and bulky structures [1][2]. Pattern reconfigurable antennas can also achieve beam scanning [3][4][5]. By employing four L-shaped antenna elements, a beam steering over 360º in the azimuth plane has been achieved in [3] with a gain around -0.5-2.1 dBi.…”

“…In [4], a rectangular single-arm spiral antenna was proposed to change its main beam over five directions with a gain between 3-6 dBi. Also, pattern reconfigurability was realized by changing the phase between two arms of a quasi-Yagi dipole antenna [5]. The beam direction can be switched to -20º, 0º, or 20º with a realized gain from 7.5 to 10 dBi.…”