【摘要】 针对微带天线带宽有限的固有不足，提出一种基于L型寄生结构的宽频带微带贴片天线。采用主辐射贴片与L型寄生贴片组合设计，整体尺寸为0.83λ0×0.83λ0×0.083λ0（λ0为中心频率5 GHz对应的波长）。主辐射贴片工作在TM10模，通过L型寄生贴片电磁耦合激发多谐振点扩展带宽，选用介电常数2.2、损耗角正切0.000 9的Rogers5880介质基板降低Q值。采用180°反相差分馈电设计抑制方向图畸变。结果表明，天线在3.6～6.6 GHz频段内电压驻波比小于2，相对带宽达60%，是传统微带天线的6倍。在6.2 GHz峰值增益为9.8 dBi，远高于一般贴片单元，工作频段内增益波动小于1.5 dB。辐射方向图在3.6～6.3 GHz频段内主瓣指向偏差小于5°，交叉极化抑制优于-15 dB，中心频点达-38 dB。该设计通过单层寄生结构实现了宽带高增益特性，适用于5G和Wi-Fi等宽带无线通信系统。更多还原

【Abstract】 To overcome the inherently narrow bandwidth of conventional microstrip antennas, this work proposes a wideband microstrip patch antenna using an L-shaped parasitic structure. The antenna consists of a main radiating patch and L-shaped parasitic elements, with an overall size of 0.83λ0×0.83λ0×0.083λ0, where λ0 denotes the free-space wavelength at the 5 GHz center frequency. The main patch operates in the fundamental transverse magnetic(TM₁₀) mode, while multiple resonances are introduced via electromagnetic coupling with the parasitic elements, thereby significantly extending the bandwidth. A Rogers 5880 substrate with a relative permittivity of 2.2 and a loss tangent of 0.000 9 was used to reduce the quality factor. A 180° out-of-phase differential feeding scheme was applied to suppress radiation pattern distortion. Simulation results show that the proposed antenna achieves a voltage standing wave ratio（VSWR） below 2 from 3.6 GHz to 6.6 GHz, corresponding to a 60% fractional bandwidth—six times wider than that of traditional microstrip designs. The antenna exhibits a peak gain of 9.8 dBi at 6.2 GHz, with gain variation within 1.5 dB across the operating band. The main beam remains stable, with a pointing deviation within 5°, and cross-polarization levels remain below-15 dB over 3.6 GHz to 6.3 GHz, reaching as low as-38 dB at the center frequency. This single-layer configuration achieves both broadband and high-gain performance, demonstrating strong potential for broadband wireless applications, including 5G communication and Wi-Fi systems.更多还原