Miniaturised rat‐race coupler with second and third harmonic suppression using synthesised transmission lines. Issue 22 (1st October 2013)

• Record Type: Journal Article
• Authors: Lai, C.‐H.; Ma, T.‐G.
• Is Part Of: Electronics letters. Volume 49:Issue 22(2013)
• Page Start: 1394
• Page End: 1396
• Publication Date: 2013-10-01
• Subjects: capacitors -- harmonics suppression -- slow wave structures -- transmission lines -- waveguide couplers; miniaturised rat‐race coupler -- second harmonics suppression -- third harmonics suppression -- slow‐wave synthesised transmission lines -- Ï€‐networks -- parallel LC tank -- shunt capacitors -- transmission zero -- harmonic attenuation -- compact footprint -- frequency 2.4 GHz; Electronics -- Periodicals; 621.381
• DOI: 10.1049/el.2013.2975
• Languages: English
• ISSNs: 0013-5194

Abstract

Abstract : A miniaturised rat‐race coupler capable of suppressing the second and third harmonics is proposed. The coupler is designed with slow‐wave synthesised transmission lines using two π ‐networks in cascade. Each π ‐network is formed by a parallel LC tank and two shunt capacitors, and is associated with a transmission zero for harmonic attenuation. The two transmission zeros embedded in the synthesised line can be controlled independently. The proposed rat‐race coupler, centred at 2.4 GHz with an operational bandwidth of 18.8%, and at least 21‐dB suppression at the second and third harmonics, features a compact footprint, which is only 12.9% the size of its conventional counterpart.