Research Showcase Gallery (Poster 2105)

High Isolation Log-Periodic Dipole Array System with High Isolation for Wideband Full-Duplex Applications

Abstract

As the rapid increments of hand-held technologies, the radio wave spectrum is becoming increasingly congested. The current data transmission practice causes the congestion of the spectrum, such as full-division duplexing, where the data transmit and receive operations are working at different frequencies. In order to minimize the congestion, full-duplex communications is being developed which is attempting to enable transmit and receive operations at a single frequency simultaneously. Because the transmitted and received signals are reduced down to a single frequency, more frequency resources will be available for the data communication within a specified bandwidth. In this study, we propose a differentially driven log-periodic dipole array (LPDA) system with high isolation between reception and transmission ports for wideband full-duplex applications. LPDAs are widely used in wireless applications due to their broad bandwidth, low cross polarization, high gain, and highly directive patterns. The antenna system is comprised of two pairs of conventional LPDAs operating in the X-band spectrum from 8 GHz to 12 GHz. The simulation results show high isolation S21 < - 60 dB through the entire X-band while the measured results reach S21 < - 50 dB in a reflective lab environment. The system offers a low cross-polarization for both transmit and receive modes (less than - 25 dB). The design is able to cover 360º direction with reasonable gain values, high efficiency, and good impedance matching. The proposed design provides a coverage for X-band spectrum which has common applications in radar, weather monitoring, or air traffic control.


About the Presenter

photo of tuan nguyen

Tuan Nguyen

Tuan Nguyen received the B.S. degree in electrical engineering from Washington State University, Vancouver, WA. He is currently pursuing the M.S. degree in electrical engineering with emphasizing in RF antenna design at School of Engineering and Computer Science, Washington State University, Vancouver, WA, USA.