Switched-beam antenna array design for millimeter-wave applications

The limited coverage of wireless communication at the millimeter-wave frequency band due to large free-space path loss, i.e. large signal attenuation, has been a major problem. Furthermore, shadowing and small-scale fading may reduce the received signal even more. An array of rod antennas is designed to tackle those problems by providing high gain, broad scan range, and a shaped beam. Each patch, which couples the electromagnetic wave to the rod, is fed by a coplanar waveguide (CPW) feedline. Each rod antenna demonstrates 18 dBi realized gain and 20° half power beamwidth (HPBW). Moreover, the 4 GHz bandwidth of the antenna provides high data rate for the gigabit wireless application. Furthermore, the Radio Frequency Microelectromechanical System (RF MEMS) switch is used to realize a switched antenna with a broad scan range. The design method and the characterization of the antenna are presented. The proposed antenna system is suitable for a wide range of applications, such as wireless high definition video/audio, USB and firewire replacement, Frequency Modulated Continuous Wave (FMCW) radar, and home/office backhaul application at millimeter-wave frequency

Dual-circularly-polarized balanced-fed dielectric rod antenna for 60-GHz point-to-point wireless communication

The design of a dual-circularly-polarized balanced-fed dielectric rod antenna for 60-GHz point-to-point communication is described and realized. The measured gain and axial ratio are 15dBi and below 0.5dB, respectively

A millimeter-wave tapered dielectric rod with two-antenna excitation for same frequency duplex operation

In this paper, 60-GHz dielectric rod¿s excitation techniques are proposed and designed. Two adjacent decoupled patch antennas are used as excitation to the dielectric rod. Each antenna performs either Tx or Rx operation, in such a way simultaneous duplex operation can be done at the same frequency. Dual-sense circular polarization is here employed to realize that duplex wireless communication. The Tx-to-Rx isolation achieves better than 30 dB for the whole 60-GHz ISM frequency band. The axial ratio is maintained below 3 dB, and the antenna gain is more than 9 dBi. Two positional antenna configurations are here proposed for the end-to-end antenna testing, i.e. one configuration is for the one end while another configuration is for the opposite end. This is useful to keep the position of the electronics (behind the antenna) uniform

60-GHz wideband branchline coupler and patch antenna with dielectric rod for full-duplex gigabit wireless communication

An improved design of the patch antenna with the dielectric rod is proposed. The wideband branchline coupler and wideband patch antenna are designed and optimized to realize a high port-to-port isolation for the whole 60-GHz ISM frequency band. In this paper, the design of the improved dielectric rod antenna is explained. The achieved gain of the antenna system is around 13.5 dBi, and the antenna supports dual circular polarization for bi-directional communication while promotes rotational freedom. The achieved port-to-port isolation larger than 20 dB is obtained for the bandwidth of 7 GHz, which is a significant improvement from the author's previous design. The measured axial ratio in the bandwidth of interest is below 3 dB

High performance 60-GHz dielectric rod antenna with dual circular polarization

In this paper, the design of a high performance dielectric rod antenna is described and validated through measurements. The manufactured 60-GHz dielectric rod antenna has the predicted gain of around 15 dBi and supports dual circular polarization. The lateral dimension of the rod antenna is very small in comparison to its counterparts. The measured port-to-port isolation larger than 20 dB is obtained for the bandwidth of 1.1 GHz. The measured axial ratio (AR) in the bandwidth of interest is below 0.5 dB. It will be shown that the very wideband return loss is due to the quadrature hybrid coupler

Wideband dual-circularly-polarized dielectric rod antenna for applications in V-band frequencies

In this paper, two improved 60-GHz dielectric rod’s excitation technique are designed. Two adjacent decoupled patch antennas are used as excitation to the dielectric rod. Each antenna performs either Tx or Rx operation, in such a way simultaneous duplex operation can be done at the same frequency. Dual-sense circular polarization is here employed to realize that duplex wireless communication. Tx-to-Rx isolation achieves better than 30 dB for the whole 60-GHz ISM frequency band. The axial ratio is maintained below 3 dB, and the antenna gain is more than 9 dBi. Two positional antenna configurations are proposed for end-to-end antenna testing, i.e. one configuration is for one end while another one is for the opposite end. This is useful to keep the position of the electronics (behind the antenna) uniform