A novel self‐packaged DBBPF with multiple TZs for 5G sub‐6 GHz applications

Abstract

In this article, we proposed a self‐packaged dual‐band bandpass filter (DBBPF) with high isolation and low insertion loss (IL) for 5G sub‐6 GHz applications. To get high stopband suppression, multiple and controllable transmission zeros (TZs) are introduced. A pair of quarter‐wavelength stepped‐impedance resonators (QSIRs) and half‐wavelength hairpin resonators (HWHR) are introduced to form a cross‐coupled five‐star topology to generate two passbands and multiple TZs analyzed by mixed electromagnetic couplings. A pair of U‐shape resonators are designed on G6 to fully excite the resonators and introduce source/load TZs at the same time. The generation of TZs by separate electric and magnetic coupling paths (SEMCP) is discussed. The DBBPF achieves a low IL of 0.85/1.13 dB with fractional bandwidths (FBW) of 11.0%/6.9% at center frequencies of 3.45 and 4.9 GHz for 5G sub‐6 GHz applications, respectively. The total size is only 0.32 λg × 0.45 λg.

Regulation and Control of Electromagnetic Field in Radio-Frequency Circuits and Systems

“…implemented in [41] and [42] by using a similar method of physical path separation. The structure of the main coupling pattern of the stepped-impedance resonator (SIR) in [41] and the topology are shown in Figure 20.…”

“…implemented in [41] and [42] by using a similar method of physical path separation. The structure of the main coupling pattern of the stepped-impedance resonator (SIR) in [41] and the topology are shown in Figure 20. This filter introduces multiple zeros by using a combination of physical path separation and source-load coupling.…”

Self‐packaged MISL‐based miniaturized high Q factor bandpass filter

“…Its wider cross-section, when compared to a microstrip or coplanar line, results in lower current densities in the circuits and lower electric-field strength in the dielectric, thereby achieving low losses. In recent years, the SISL technique has been widely proposed and used for the design of microwave circuits with enhanced performance [1][2][3][4][5][6][7][8][9].…”

Novel 6‐GHz/80.8% fractional bandwidth filtering power divider with ultra‐large coupling coefficient using air‐dielectric broadside‐coupled lines

“…Substrate integrated suspended line (SISL) can exhibit lower loss based on the FR4 substrates because more electric field is distributed in the embedded air cavity rather than in the lossy substrate. [13][14][15][16][17] However, in the several published SISL filter circuits, single inner circuit layer is always used, which cannot achieve air-dielectric broadside coupling. 13,14,16 Therefore, improvement should be made on the traditional SISL structure.…”

“…[13][14][15][16][17] However, in the several published SISL filter circuits, single inner circuit layer is always used, which cannot achieve air-dielectric broadside coupling. 13,14,16 Therefore, improvement should be made on the traditional SISL structure. Until now, high frequency and large coupling coefficient FPD with airdielectric broadside-coupled Lines is rarely reported.…”