本文为英国杜伦大学（作者：Xavier Zage Raimundo）的博士论文，共247页。
线性/步进调频连续波（FMCW）信号在雷达和信道探测中的应用由来已久。本文提出了一种新的FMCW波形，称为“门控FMCW”信号，用于抑制微波雷达应用中的强非期望信号，如穿墙雷达、探地雷达和医学成像雷达。在这些应用中，天线之间的串扰信号和来自早期界面（壁面、地面或皮肤）的反射信号在数量上比来自目标的后向散射信号强得多。因此，如果不加以抑制，它们会掩盖目标的返回，使探测成为一项困难的任务。此外，这些强的不需要的反射限制了雷达的动态范围，可能会使接收机饱和或阻塞，从而导致来自实际目标（特别是低雷达截面目标）的反射显示为噪声。通过数值模拟和实验，研究了该波形作为一种抑制技术在各种雷达场景中的有效性。文中还对标准线性调频连续波信号和所提出的门控调频连续波波形下的雷达图像进行了比较。除雷达外，还描述了FMCW信号在室内和室外环境中60GHz、2 – 6GHz频段的无线电传播测量和信道特性。利用这些数据预测了内部构建的基于测量的信道模拟器的误比特率性能，并将结果与Matlab中的理论多径信道模拟器进行了比较。
A linear / stepped frequency modulatedcontinuous wave (FMCW) signal has for a long time been used in radar andchannel sounding. A novel FMCW waveform known as “Gated FMCW” signal isproposed in this thesis for the suppression of strong undesired signals inmicrowave radar applications, such as: through-the-wall, ground penetrating,and medical imaging radar. In these applications the crosstalk signal betweenantennas and the reflections form the early interface (wall, ground surface, orskin respectively) are much stronger in magnitude compared to the backscatteredsignal from the target. Consequently, if not suppressed they overshadow thetarget’s return making detection a difficult task. Moreover, these strongunwanted reflections limit the radar’s dynamic range and might saturate orblock the receiver causing the reflection from actual targets (especiallytargets with low radar cross section) to appear as noise. The effectiveness ofthe proposed waveform as a suppression technique was investigated in variousradar scenarios, through numerical simulations and experiments. Comparisons ofthe radar images obtained for the radar system operating with the standardlinear FMCW signal and with the proposed Gated FMCW waveform are also made. Inaddition to the radar work the application of FMCW signals to radio propagationmeasurements and channel characterisation in the 60 GHz and 2-6 GHz frequencybands in indoor and outdoor environments is described. The data are used topredict the bit error rate performance of the in-house built measurement basedchannel simulator and the results are compared with the theoretical multipathchannel simulator available in Matlab.
- 引言与重要性
1.1 回顾概述
1.2 论文贡献
1.3 本文组织结构
1.4 参考文献 - 雷达原理
2.1 基本雷达方程
2.2 传统雷达系统
2.3 传播效应
2.4 成像算法
2.5 小结
2.6 参考文献 - 杂波抑制技术：回顾
3.1 基于后处理的技术
3.2 基于硬件的技术
3.3 本文提出的杂波抑制技术
3.4 小结
3.5 参考文献 - 门控FMCW信号原理
4.1 FMCW信号
4.2 门控频率调制连续波波形
4.3 小结
4.4 参考文献 - 硬件实现
5.1 基于AWG的GFMCW雷达系统
5.2 基于VNA的GFMCW雷达系统
5.3 时钟源与同步单元
5.4 X-Y定位器系统
5.5 UWB天线
5.6 小结
5.7 参考文献 - 数值雷达仿真
6.1 CST（MWS）中基于Chirp的雷达仿真
6.2 仿真结果
6.3 小结
6.4 参考文献 - 无线电成像的实验结果
7.1 穿墙成像雷达
7.2 探地雷达
7.3 医学成像雷达
7.4 小结
7.5 参考文献 - 结论与未来工作展望
8.1 结论
8.2 未来工作展望
附录A 雷达的MATLAB代码
附录B X-Y定位器及代码
附录C 信道特性与性能预测
附录D 发表论文列表
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