Measuring of thickness of the asphalt pavement with Use of GPR
The results of development, tests and application of the GPR for measurement of the road asphalt layers thickness are presented in the paper. Main necessary improvements providing the possibility of use the GPR as a measuring device are described as well as some results of application of the GPR for inspection of the road structure after reparation the road. It was achieved accuracy of layers thickness measurement better than 0.5 cm.
Measurements of antenna properties in time domain
The authors of this work have designed, manufactured, tested and applied an ultra-wideband measurement system (MS) for investigating characteristics of antennas in the operating frequency band of up to 2 GHz. The synamic range of the measured signals is at least 80 dB. The use of fairly strong signals for excitation of radiating antenna extends the power budget by 40 dB else. The absence of reflections from interfering objects in the test signal enabled us to utilize the entire dynamic range. In the paper; features of instrumentation are briefly described, and an example of measurement results is presented.
High decoupled antenna for UWB pulse GPR “ODYAG”
A principle of operation and arrangement of UWB antenna system which differs from other with very high frequency independent electromagnetic decoupling are described in the paper. Peculiar design of the antenna makes it possible to use it in two different modes - horizontal scanning mode and accurate definition of local object location mode. The antenna system is designed for the ground penetrating radar ldquoODYAGrdquo monitoring of subsurface structure of asphalted roads.