提出了一种应用于海事卫星通信海上宽带系统终端的圆极化叠层微带天线,该天线选用廉价FR4板、空气介质和对角线切角的正方形贴片组成叠层结构,采用不等功率四馈电技术激励主辐射贴片,展宽了天线的阻抗带宽和轴比带宽。文中给出了设计思路,并利用电磁仿真软件HFSS分析了天线性能,仿真与测试结果吻合良好。结果表明:天线具有良好的性能,VSWR≤1.5的阻抗带宽测量值达23.4%(1453~1838MHz),轴比小于3dB的圆极化带宽仿真值达25.6%(1360~1760MHz)。在海事卫星工作频段内VSWR小于1.2,轴比小于1.5dB,增益大于9dBi。所设计的天线满足Fleet Broadband系统FB150业务的需求。
A novel broadband circularly polarized stacked patch antenna is proposed for INMARSAT Fleet Broadband system terminal applications.The antenna is composed of two corner truncated patches and an unequal power feeding network(UPFN),all of which are printed on the double side of the FR4 substrates.The four output ports of UPFN are connected to the main radiating patch by four probes,while the input port is connected to an SMA connector.Using the proposed unequal power feeding technique,a good impedance matching and low axial ratio(AR) can be achieved.Simulation results are compared with those measured,and a good agreement is obtained.The measurements show that the antenna has an impedance bandwidth(VSWR1.5) of about 23.4%(1453~1838MHz),a 3dB AR bandwidth of about 25.6%(1360~1760MHz).During the INMARSAT operating band,the VSWR is lower than 1.2,the AR is lower than 1.5dB,and the gain is higher than 9dBi.Therefore,the proposed antenna can be a good candidate for Fleet Broadband FB150 system.