文档介绍：DESIGN AND PERFORMANCE OF A NOVEL BROADBAND UNIPLANAR BALANCEDSUBHARMONIC MIXER
ABSTRACT: A novel wideband uniplanar balanced subharmonic mixer is proposed and demonstrated. The mixer is based on the broadband tapered coplanar-waveguide (CPW) DC-block filter, and the in-phase and out-of-phase T-junctions are interconnected through a pair of quarter-wavelength slotlines. The fabricated subharmonic mixer has an RF bandwidth of more than one octave from 12 to 28GHz with a conversion loss ranging from to dB for LO signals from to GHz with a power level of dBm. The measured LO-to-RF, LO-to-IF, and RF-to-IF isolations are better than , 34, and dB, respectively. . 2005 Wiley Periodicals, Opt Technol Lett 44: 508 –510, 2005; Published online in Wiley InterScience. DOI
Key words: balanced subharmonic mixer; broadband uniplanar technology; coplanar waveguide; slotline; microwave integrated circuits
1. INTRODUCTION
Uniplanar technology has received considerable attention with regard to low-cost and high-performance microwave integrated circuits (MICs) and microwave monolithic integrated circuits (MMICs), especially in the millimeter-wave range [1–3]. This is due to the merits not requiring via holes for connecting circuit elements to the ground, elimination of the backside processes, simple realization of series and shunt ponents, easy integration with solid-state devices and other lumped elements,and low sensitivity to substrate thickness [4]. Furthermore, this technology allows flexible circuit design using mixed transmission lines such as coplanar waveguide (CPW), slotline, and coplanar stripline. Subharmonic mixing is very useful at millimeter wave frequencies due to the availability of low-cost lower-frequency local oscillators (LOs). Balanced subharmonic mixers have the advantages of the inherent LO-to-RF isolation and the reduction of LO noise and spurious signals [5].
Recently, a few balanced subharmon