Ground Penetrating Radar Signal Processing In Advanced Detection In Coal Seam

In the coal mining, because the coal seam may contain groundwater or gas cavity, whendisaster occurs, it will seriously threaten the miners and the equipment safety. The use ofadvanced detection of ground penetrating radar(GPR) in the work surface can pre-judge thehidden danger in the mining, and has important research significance.According to the characteristics of coal medium, through the analysis of absorptionattenuation and reflection attenuation of the electromagnetic wave in coal medium, we can getthe loss characteristics in the electromagnetic wave propagation, through the analysis offrequency modulated continuous wave GPR working principle, target formula for single targetdetection is derived; According to the transfer equation of GPR signal, through the analysis ofFMCW-GPR step frequency increment and the range resolution and maximum unambiguousrelation between distance and range resolution, the maximum detection range of conflicts, theground is the simulation of radar transmitting power and detection distance, the lowerfrequency is the effective measures to reduce the transmission power or increase the detectiondistance.According to the application of ground penetrating radar to advance detection of coalseam two main tasks--location and identification of target, multiple signal classification basedon the target medium positioning and research algorithm research target medium identificationbased on echo intensity. Through the analysis of FMCW-GPR signal, select the MUSICalgorithm to deal with the echo signal, the simulation results show that, for the non correlationsignal, signal length is longer, the received signal to noise ratio is greater, receiving antennaarray element number, the resolution of the algorithm is higher. the normalized frequencyin(3-4)π/100, MUSIC recognition algorithm is suitable for multiple signal. And for thecorrelation signal, the performance of MUSIC algorithm becomes very bad, this paper proposes an improved MUSIC algorithm based on correlation signal processing, simulationresults show that, the improved MUSIC algorithm can achieve accurate estimation ofcorrelated signals, achieve the target positioning purposes. Through the analysis on thecharacteristics of electromagnetic wave loss in coal seam, with dangerous source in coal seamspecies, deduces the relationship between the seam in different dielectric loss and dielectricconstant, the echo target recognition algorithm based on the medium intensity, the analysis andsimulation results show that the algorithm in coal seam water, air, rock better resolution, caneffectively predict the water or gas cavity coal seams in the unknown, achieve the targetidentification purposes.This study provides a theoretical basis for the development of geophysical technology, andthe study have a certain application value in advanced detection in coal seam.