缝隙波导谐振阵最大带宽分析方法研究

Research on Maximum Bandwidth Analysis Method of Slotted Waveguide Resonant Array

文中基于波导并联缝隙的RLC串联等效电路,建立了谐振阵阻抗带宽的通用分析方法,对单一过载和过载匹配两种设计条件下谐振阵的最大带宽进行了研究,给出了最优带宽拟合公式并确定了相应匹配条件下的导纳特性,系统解决了谐振阵阻抗带宽的设计边界与设计方向问题。最后结合缝隙等效电路,提出了一种新颖的导纳特性调整方法,通过引入平行隔栅控制缝隙导纳的电容特性,利用过载匹配技术实现了8单元中心馈电谐振阵的最大带宽设计。全波仿真结果显示,VSWR≤1.5时的最大带宽可达到16.2%,相应的电容参数C为4.9 pF,该结果与拟合公式得到的电容参数C及最大带宽计算数据较为一致,并且缝隙归一化导纳特性的全波仿真数据与等效电路优化出的最佳导纳特性的吻合性非常好。最后设计了一个8×8试验阵并展开了测试,该试验阵VSWR≤1.5时的工作带宽为16.4%,与全波仿真结果及等效电路分析结果均较为一致,证明了文中提出的谐振阵的带宽分析方法是准确可行的。

Based on the RLC series equivalent circuit of waveguide parallel slots,a general analysis method for the impedance bandwidth of the resonant array is established in this paper.The maximum bandwidth of slotted waveguide resonant array under the single-overload and overload-matching conditions is studied;two fitting formulas for optimal bandwidth are given.By confirming the required admittance characteristics for different matching conditions,the design limitation and direction of resonant array impedance bandwidth can be systematically solved.Combined with equivalent circuit of slot,a novel method for adjusting the admittance characteristics is proposed.By introducing parallel fence to control the capacitive parameters of slot admittance,the maximum bandwidth design of 8-unit center-fed resonant array is realized using overloadmatching technology.The full-wave simulation results show that when VSWR≤1.5,the maximum bandwidth can reach 16.2%,and the corresponding capacitance parameter C is 4.9 pF.This result is consistent with the corresponding data obtained by the fitting formula,and the full-wave simulation of the slot normalized admittance characteristics are in good agreement with the optimal data optimized by the equivalent circuit.Finally,an 8×8 array is designed and tested.When VSWR≤1.5,the bandwidth of the array is 16.4%,which agree with the full-wave simulation results and the equivalent circuit analysis results,proving that the bandwidth analysis method of the resonant array proposed in this paper is accurate and feasible.