文档介绍：外文原文
Compact Multi-harmonic harmonic suppression
Compact Multi-harmonic suppression Bandpass Filter Using Parallel Short-Ended Coupled-Line Structure Xu-Guang Wang, Young Yun, and In-Ho Kang This paper presents a novel simple filter design method based on a parallel short-ended coupled-line structure with capacitive loading for size reduction and ultra-broad rejection of spurious passbands. In addition, the introduction of a cross-coupling capacitor into the miniaturized coupled-line can create a transmission zero at the second harmonic frequency for better frequency selectivity and attenuation level. The pensation technique is also applied to achieve a strong coupling in the coupled-line section. The influence of using the connecting transmission line to cascade two identical one-stage filters is studied for the first time. Specifically, such a two-stage bandpass filter operating at GHz with a fractional bandwidth of 10% was designed and realized with low-temperature co-fired ceramic technology for application in base stations that need high power handling capability. The measured and simulated results showed good agreement. Keywords: harmonic bandpass filter, . suppression, coupled-line, I. Introduction In recent years, compact, high-performance, and low-ponents for radio frequency (RF) applications have been the focus of a great deal of research and industrial pursuit with the explosive growth of modern munication services. One promising method for many miniaturizing and packaging technologies is to use low-temperature cofired ceramic () on account of its multilayer structure and high unloaded quality factor. The bandpass filter is an ponent in the RF front-end munication systems. It passes the desired frequencies, rejects unwanted signals, and suppresses harmonics. However, as a result of the distributed characteristic of the transmission line, undesired spurious passbands or harmonics are a problem for conventional filters and can seriously degrade th