| 1. | Effects of random errors on the sidelobe level of a module array antenna 随机误差对模块化阵列天线副瓣的影响 |
| 2. | It is shown that the lower sidelobe level of multi - step amplitude quantized array should be achieved using the fewer number of quantized steps 研究结果表明,利用较少量化台阶数,多阶振幅量化阵可实现较低的副瓣电平。 |
| 3. | Fir filters with special frequency responses are designed using a modified adaptive design approach for a practical broadband low sidelobe level beamforming problem in time domain 采用改进的fir数字滤波器自适应设计方法,设计了具有特殊频率响应结构的fir数字滤波器。 |
| 4. | We studied the characteristic of the signals and processing methods . spatially variant apodization algorithm is introduced to significantly reduce sidelobe levels without degrading mainlobe resolution 用sva的方法对回波信号加权,在有效抑制isar回波脉冲包络旁瓣电平的同时提高信号的主瓣分辨率。 |
| 5. | Performance of inflatable antenna reflector hinges critically on the precision of the membrane surface . if the error is not in the range of limit , it will heavily decrease antenna gain and increase sidelobe level 形面精度是决定充气展开天线反射器性能的一个关键因素,如果误差不在允许范围内,那么它会严重降低天线的增益,增加旁瓣电平。 |
| 6. | The processing of these hybrid signals is different from the single modulation signal , that is pulse compression twice . with respect to the hybrid signals including sf , the high range resolution is analysis , and the method for reducing sidelobe level is 对于与频率步进信号复合的组合脉压信号,分析了它们的合成高距离分辨效果,并对其距离旁瓣的抑制方法进行了探讨。 |
| 7. | Lake - experiment verified the correctness of this low sidelobe level beamformer . 4 . the broadband constant beamwidth beamforming vectors for a uniform linear array are designed and its effectiveness when applied to a real array is verified by water tank experiment 针对均匀分布线列阵,设计了基于chebyshev加权的宽带恒定束宽波束形成向量,消声水池实验验证了设计方法对于实际基阵的有效性。 |
| 8. | Fsk / psk radar signal is the signal with both fsk and psk modulation at one time . it is with large bandwidth time product ( bt ) , thumbtack - like ambiguity function and well ability of anti - emi . the fsk / psk signals of which the frequency - hopping and bi - phase sequences were randomly chosen often have high sidelobe level Fsk / psk信号是同时进行频移键控( fsk )和相移键控( psk )调制的信号,该信号具有大时带宽积( bt )和高分辨特性,并具有“图钉型”模糊图结构、低截获概率( lpi )特性和较好的抗干扰能力,受到了广泛的重视。 |
| 9. | A patch antenna with air holes in the substrate has been designed . the finite - difference time - domain ( fdtd ) method together with the perfectly matched layer ( pml ) boundary treatment has been used to study the performance of the antenna . it is shown that the surface waves are significiently suppressed , the frequency bandwidth is improved , the sidelobe levels are reduced and consequently the gain in the forward direction is improved by 14 db ( about 4 db higher than the value reported previously ) 设计了一种基底钻周期圆孔结构的电磁(光子)晶体贴片天线,用fdtd方法并结合pml吸收边界条件对该天线进行了研究,结果表明本文所设计的基底钻孔型电磁晶体贴片天线取得了多方面的性能改善,与普通天线相比,基底中的表面波受到很大抑制,天线的带宽增加,远场方向图上天线的旁瓣和背瓣被明显削弱,向前辐射的增益由原来的12db增加到26db ,增加了14db ,比文献上报道的gonzalo等人的研究结果提高了4db 。 |
| 10. | Combining the above signal model and the conventional lcmv method at element level we present a lcmv method at subarray level . in all kinds of jammer scenarios , the method can suppress jammers well , but the disadvantage is that the sll ( sidelobe level ) of adaptive patterns is much higher 将上述提出的信号模型与常规线性约束最小方差( lcmv )方法相结合得到子阵级lcmv方法,在各种干扰情况下该方法都可以实现对干扰的很好抑制,但其局限性是自适应方向图的旁瓣电平较高。 |