Tracking rebar in concrete: estimating the power required for gpr

[مهرداد کریمی‎]

Hi everyone.

    I tried to place two rebars with a diameter of 3 cm in a depth of 4 meters of concrete. Then with Hertzian dipole source and placing some rx in different positions, I tried to get the ratio of the received signal to the transmitted signal t.
    My main goal is the ratio of returned power to transmitted power. (This is the first stage of the initial simulation to estimate the power required for this application)
This is my code.

#Title: Hertzian dipole _ tow cylinder at a depth of 4 meters in concrete

#domain: 0.3 0.40 4.3
#dx_dy_dz: 0.0025 0.0025 0.0025

#time_window: 80e-9
#waveform: contsine 300 8e8 my_sine

#hertzian_dipole: x 0.15 0.175 4.2 my_sine 0 30e-9

#material: 4.5 1e-2 1 0 concrete
#box: 0 0 0 0.3 0.3 4.1 Concrete y
#cylinder: 0 0.05 0.05 0.3 0.05 0.05 1.5e-2 pec y
#cylinder: 0 0.35 0.05 0.3 0.35 0.05 1.5e-2 pec y

#rx: 0.15 0.175 4.2
#rx: 0.15 0.175 4.15
#rx: 0.15 0.175 4.05
#rx: 0.15 0.175 2.05
#rx: 0.15 0.175 0.05
#rx: 0.2 0.175 4.2
#rx: 0.2 0.175 4.25
#geometry_geometry: 0 0 0 0.3 0.35 4.3 0.0025 0.0025 0.0025 hertzian_dipole f

    But the simulation results are a bit strange. Although the transmitted signal stops after a while, I have a continuous received signal like noise, which does not look like a rebar reflection at all. Or I do not receive at all.
My questions are:
Is my path to get this power a reasonable way?
Is there a better way to estimate the required power of the device in gprmax software?
Does the signal have enough range?

Can anyone introduce me to a better way or help me with possible problems with this simulation?

Mehrdad Karimi
Nit University