Research Of New Technology In Hidden Target Time Domain Multi-Channel Detecting System

In this thesis, hidden target time domain multi-channel detecting system isdiscussed. The system can be used to detecting the underground target, such as mineclearance, geological prospecting, highway subgrade detection, urban undergroundpipeline detection. Besides, it also can be applied to searching for target hidden on theground, such as TWD (through-wall detecting), building quality testing, target detectionin jungle environment. Detecting the hidden targets by time domain pulse has become toone of research hotspots in radar detecting field. It has vast potential for futuredevelopment.In the thesis, this constitution theory of the detecting system is discussed in detail.The important components, such as ultra-wide band (UWB) time domain pulse antenna,high magnitude multiple cascaded time domain narrow pulse signal, time domainmulti-channel receiver, are researched much deeper. Based on analyzing many kinds ofUWB antennas and generalizing the influence of antenna parameters, a trapezoidalcavity-backed resistance loaded bow tie time domain antenna is designed. The error oftime domain pattern is also revised during the research of time domain UWB array.Matching technique (between antennas and impulse source) and multi-cascaded circuitis proposed. Besides, the balanced output source with ten thousand volts is developed tomatch with antenna. Then, based on designing time domain multi-channel receiver oftime sharing processing, the experimental prototype of hidden target time domainmulti-channel detecting system is manufactured. All of them are proved to work steadilyand effectively. Finally, electromagnetic time reversal (EMTR) algorithm is applied torealize super-resolution focus positioning imaging of target.The thesis is constituted as follows: first, the research background of hidden targettime domain multi-channel detecting system is introduced. Then, constitution theory ofthe detecting system is presented. After that, the designs of UWB time domain pulseantenna and time domain multi-channel receiver are proposed. Besides, the experimentprototype is tested in multiple scattering complex environments. Finally, the conclusionsand the following work are suggested. The major contributions and innovations are followed as,1. Symmetrical multi-cascaded solid pulse source with high power is proposed. Itis tested to well in the detecting system.2. The gradual back cavity design is first proposed in the field of time domainUWB antennas. It doesn't only improve time domain performance of resistance loadedbow tie antenna, but also elevates the isolation between the receiving and transmittingelements3. In the time domain pattern measurement, the revised algorithm of patternmultiplication is raised to minimize the error. Therefore, the precision of target locationis elevated effectively.4. The optics time domain detecting device is applied for enlarging the magnitudeof pulse resource in the system. So, the longer distance and higher isolation areguaranteed.5. Time domain multi-channel receiver of time sharing processing is developed fordecreasing the cost of time domain detecting system. Feasible way is also given forenlarging antenna caliber and developing three dimensional localizations in the nextwork.