Performance Optimization and MALA_1200 and GSSI_1500 Compatibility in gprMax v3.1.7

[杨天宏]

  Hello,

Hope you are well and thanks for providing this great software. I have two questions:

1. Performance Optimization with GPU:
Despite using a GPU (GTX 1660) for simulation, the generation speed remains slow for large datasets (e.g., 5000 simulations). For instance, a single simulation with 76 A-scans takes approximately one hour. One contributing factor is the extremely high temporal resolution: gprMax generates around 15,000 time samples per A-scan, which is much finer than typical real-world GPR systems (usually 256–1024 samples). 

Question: Without upgrading the GPU, are there effective strategies to accelerate simulations while preserving sufficient time window (to maintain adequate penetration depth)? Specifically, can I safely reduce the number of time samples by adjusting parameters such as dt (time step) or time_window, and if so, what are the recommended practices to ensure simulation validity?

crack_model_1_input.in

#title: Road_Model_Distress
#domain: 4 1.8 0.001
#dx_dy_dz: 0.001 0.001 0.001
#time_window: 15000
#time_step_stability_factor: 0.99
#waveform: ricker 1 500e6 my_pulse
#hertzian_dipole: z 0.1 1.7 0 my_pulse
#rx: 0.2 1.7 0
#src_steps: 0.01 0.000 0.000
#rx_steps: 0.01 0.000 0.000
#geometry_objects_read: 0 0 0 crack_model_1_h5file.h5 crack_model_1_materials.txt
geometry_view: 0 0 0 4 1.8 0.001 0.001 0.001 0.001 Road_Model n

or

crack_model_1_input.in

#title: Road_Model_Distress
#domain: 4 1.8 0.001
#dx_dy_dz: 0.001 0.001 0.001
#time_window: 30e-9
#waveform: ricker 1 500e6 my_pulse
#hertzian_dipole: z 0.1 1.7 0 my_pulse
#rx: 0.2 1.7 0
#src_steps: 0.01 0.000 0.000
#rx_steps: 0.01 0.000 0.000
#geometry_objects_read: 0 0 0 crack_model_1_h5file.h5 crack_model_1_materials.txt
geometry_view: 0 0 0 4 1.8 0.001 0.001 0.001 0.001 Road_Model n

2. Antenna Model Compatibility (MALA_1200 and GSSI_1500):
When using built-in antenna models such as  MALA_1200 or GSSI_1500, is there a minimum domain size requirement? Specifically, must the "#domain" dimensions be larger than the physical size (casesize) of these antenna models? 

I used the "crack_model_1_input_MALA_1200.in" and encountered the following error:

Traceback (most recent call last):
  File "f:\MySoftware\Anaconda\anaconda3\envs\gprMax\lib\runpy.py", line 196, in _run_module_as_main
    return _run_code(code, main_globals, None,
  File "f:\MySoftware\Anaconda\anaconda3\envs\gprMax\lib\runpy.py", line 86, in _run_code
    exec(code, run_globals)
  File "f:\MySoftware\Anaconda\anaconda3\envs\gprMax\lib\site-packages\gprmax-3.1.7-py3.10-win-amd64.egg\gprMax\__main__.py", line 6, in <module>
    gprMax.gprMax.main()
  File "f:\MySoftware\Anaconda\anaconda3\envs\gprMax\lib\site-packages\gprmax-3.1.7-py3.10-win-amd64.egg\gprMax\gprMax.py", line 69, in main
    run_main(args)
  File "f:\MySoftware\Anaconda\anaconda3\envs\gprMax\lib\site-packages\gprmax-3.1.7-py3.10-win-amd64.egg\gprMax\gprMax.py", line 191, in run_main
    run_std_sim(args, inputfile, usernamespace)
  File "f:\MySoftware\Anaconda\anaconda3\envs\gprMax\lib\site-packages\gprmax-3.1.7-py3.10-win-amd64.egg\gprMax\gprMax.py", line 232, in run_std_sim
    run_model(args, currentmodelrun, modelend - 1, numbermodelruns, inputfile, modelusernamespace)
  File "f:\MySoftware\Anaconda\anaconda3\envs\gprMax\lib\site-packages\gprmax-3.1.7-py3.10-win-amd64.egg\gprMax\model_build_run.py", line 166, in run_model
    process_multicmds(multicmds, G)
  File "f:\MySoftware\Anaconda\anaconda3\envs\gprMax\lib\site-packages\gprmax-3.1.7-py3.10-win-amd64.egg\gprMax\input_cmds_multiuse.py", line 105, in process_multicmds
    raise CmdInputError("'" + cmdname + ': ' + ' '.join(tmp) + "'" + ' polarisation must be z in 2D TMz mode')
gprMax.exceptions.CmdInputError: '#voltage_source: y 1.971 1.4475 0.008 1000 myGaussian' polarisation must be z in 2D TMz mode

"crack_model_1_input_MALA_1200.in" 

#title: Road_Model_Distress_with_MALA_1200_Antenna
#domain: 4 1.5 0.001
#dx_dy_dz: 0.001 0.001 0.001
#time_window: 15000
#time_step_stability_factor: 0.99
#python:
from user_libs.antennas.MALA import antenna_like_MALA_1200
antenna_like_MALA_1200(2.0, 1.45, 0.002, 0.001)
#end_python:
#geometry_objects_read: 0 0 0 crack_model_1_h5file.h5 crack_model_1_materials.txt
geometry_view: 0 0 0 4 1.5 0.001 0.001 0.001 0.001 Road_Model n 

I would appreciate it if you could guide me on that.

Thanks,
Yang