中圖分類號：TN811+.4 文獻(xiàn)標(biāo)志碼：A DOI: 10.16157/j.issn.0258-7998.268039
中文引用格式： 楊桃均，向星誠，溫桎茹，等. 高隔離射頻濾波的PCB設(shè)計(jì)方法[J]. 電子技術(shù)應(yīng)用，2026，52(7)：24-28.
英文引用格式： Yang Taojun，Xiang Xingcheng，Wen Zhiru，et al. PCB design method for high-isolation RF filters[J]. Application of Electronic Technique，2026，52(7)：24-28.

PCB design method for high-isolation RF filters

Abstract： Traditional PCB design for RF filter circuits primarily focuses on impedance matching, with limited consideration given to the control of electromagnetic coupling paths, which restricts port isolation in filtering units. To address this, a method to achieve high isolation on PCBs based on a "field-circuit-shielding" synergistic design is proposed. This method integrates three core techniques: thinning the critical dielectric layer to enhance vertical field confinement; optimizing the coplanar ground spacing to suppress in-plane lateral coupling; and employing a high-density via array with the minimum process-achievable pitch to construct a 3D electromagnetic shielding wall. Verified through 3D electromagnetic simulation and physical measurements, the synergistic design approach improves the inter-port isolation by over 16 dB within the 1.6~2.1 GHz frequency band, without significant degradation in insertion loss. This method provides a quantitative engineering reference for the packaging and electromagnetic compatibility design of RF filtering modules and passive filters.

Key words : RF filtering；PCB design；high isolation；electromagnetic shielding；via array