The performance test of U-shape antenna applied in tunnel detection

Owing to the growth of population, thus increased land scarcity for normal surface road construct and improper city council planning it inflict more tunnel and underground structure constructed. As most of the constructed underground structures are subjected to severe adverse condition which need thorough inspection. To maintain the good inhabitable tunnel structure ground penetrating radar (GPR) always use as a measuring tools. GPR as an inspection tools in tunnel has been plague with series of setback. In this case a new type of antenna has been introduced in order to improve the performance in tunnel inspection. An emphasize part of the antenna design must be ensuring the directivity, bandwidth characteristic, radiation efficiency and the penetration depth. This research has been divided into three cases and those cases were performed in order to signify the characteristic of the antenna. Laboratory test and numerical simulation were carried out for the comparison and urged to the optimize solution. In this paper, Agilent E5060A ENA has been used for the laboratory test to examine the performance of the antenna. The FDTD method for numerical simulation is to prove the authenticity of the result of laboratory test. The test result illustrates that; the new designed antenna is suitable for tunnel inspection. The important improvement should be further carried out. Further studies must investigate the application of this type of antenna for the inspection of tunnel lining.