Design of an Active Integrated Antenna with Compact Image Rejection Mixer and Spurious Passbands Suppression of Antenna

Subject Areas : Renewable energy

Ali Reza Hazeri ¹ , Ali Reza Kashaninia ²

1 - MSc/Kermanshah Branch, Islamic Azad University
2 - Islamic Azad University, Central Tehran Branch

Received: 2009-08-15 Accepted : 2010-06-29 Published : 2012-02-01

Keywords: Active integrated antenna, compact balanced mixer, compact branch line hybrid coupler, compact image rejection mixer, IF hybrid coupler, Microstrip transmission line, Wilkinson power divider,

Abstract :

An active integrated antenna (AIA) with compact image rejection mixer (IRM) is proposed and designed. The proposed IRM is composed of 2-element microstrip rectangular patch antenna, three compact branch-line hybrid coupler (BLC), two balanced mixers, a Wilkinson power divider, and a lumped element hybrid coupler. The proposed IRM translates radio frequency (RF) (2.4 or 2.5 GHz) to two intermediate frequency (IF) and provides isolation to two possible IF. The IF and local oscillator (LO) power are chosen 50 MHz and 5 dBm, respectively. The proposed IRM is able to achieve image suppression with an isolation of approximately 20 dB. The conversion loss is lower 10 dB. The VSWR at two output ports are 1 and the VSWR at the RF port is greater than 1.8.The balanced mixer is composed of a compact BLC, two schottky diodes, two short-end stubs, and an open-end stub. By replacing the quartet-wavelength conventional transmission lines with equivalent t-type transmission line, the compact BLC  is designed, which they can suppress upper order harmonics and spurious passbands of the antenna. Miniaturize, low cost, simple circuitry, and high performance, are the main advantages to simulation this AIA with IRM. The AIA with IRM is simulated by ADS software.