NAME    radarFDTD - a full 3D simulation of electromagnetic waves with efficient    absorbing boundary conditionsSYNOPSIS    radarFDTD directory [configuration file]DESCRIPTION    When started the program needs a directory as a command line parameter.    If there is no second parameter defined it assumes the file is named    sim.cfg. After starting it will output quite a few informations about    the simulation it is going to start. The most important part is the    section about memory, do not try to run the program in the swap area,    since this will surely slow it down and may risk your hard disk which    may start to smoke after a few weeks of hard work :-(.CONFIGURATION FILE    In this section there will be a short description of all sections within    the file sim.cfg. Feel free to experiment with those settings, but do    not blame me, if something goes entirely wrong... ;-)    Since I am not a native English speaker, I hope you are not offended if    I left some mistakes in here.    Last thing, before we start: all lines which are empty or have a leading    pound sign '#' are ignored (BTW, can someone explain to me why this    double cross is called pound sign?).  VERSION NUMBER      # version number is...      3    This just states the version number this configuration file was written    for. This is checked by the program and if it does not match the    internal layout, it will not use it.  MEMORY      # maximum number of bytes the program may allocate      100000000    This is the number of bytes the program is allowed to allocate. Please    change this according to your own need (or the memory limits of your    computer; remember: this limit should be less than the physical amount    of memory installed)  MAXIMUM PML CONDUCTIVITY      # insert maximum pml conductivity here [S/m]      0.025    There is a fixed equation which rules the rise of conductivity. If you    are interested in a more detailed explanation, have a look at the paper    of Fang and Wu from 1996 (citation can be found in the README file). As    a good first guess try something between 10 and 50 mS/m, which should be    reasonable good.  MAXIMUM STRETCHING      # insert maximum pml-stretching here [1]      4.0    Stretching should prevent evanescent waves to keep on moving within the    perfectly matched layers, do not use too high values here, 2 to 4 seems    to be quite reasonable.  STEEPNESS      # insert steepness here      2.0    The higher the value for steepness is, the less reflection will occur at    the boundary between the simulation space and the absorbing layer which    is generally a good thing. But unfortunately a high value here means    that there will be a high reflection before a wave manages to reach the    layer, which is a PEC (perfectly conducting layer)  SIMULATION LENGTH      # Length of Simulation [s]      30.0e-9    This just states the overall time duration of the simulation in seconds.    Do not try to run a simulation too long, i.e. for a few seconds if your    simulation space is only a few meters wide... it will take ages  SIZE OF SIMULATION SPACE      # size of simulation space (number of boxes in x-, y- and z-direction, respectively      41 41 41    These three numbers specify how man cells are used in each direction    (let us call them x,y and z for the time being). I usually use odd    numbers, so I can place the transmitter in the very middle of the    simulation box, but handle this as you like to  CELL SIZES      # real size of a box [m] (x,y,z)      0.025 0.025 0.025    Here you specify how big (or small) a single Yee-cell should be, in this    example this is about 2.5 cm (which is roughly an inch ;-)). Be careful    with this selection, since you should have at least 10 boxes per main    wavelength you want to simulate, otherwise you might get strange wavy    things out of the simulation.  TIME STEP SIZE      # this number is a bit special: if positive it is the size of a time steps in seconds,      # if negative, a matching time step is computed via the Courant-criterion      # and finally divided by this number, i.e.