MININEC3 algorithm takes account of the real ground only for the far field calculation, which is used to obtain the beam pattern. It assumes the perfect conductive ground for the impedance calculation. In case the antenna is hooked at low height compared with the wavelength (<0,2l), the computation result is inclined to give lower Z than actual. If horizontal antenna has one (or more) wire at height <0,2l, or GP has height radials at height <0,05l,for correct definition Z you should use NEC2. In these cases use utility NEC2 for MMANA, which will calculate *.maa file with NEC2. If MMANA-GAL cannot start the calculation for some reason, you would see a message in the right upper log window. This mostly is due to something wrong in your antenna definition. Recheck your antenna definition. For the F/B calculation, MMANA-GAL uses the values in the range, the right back to 120 degrees, and compares them with the worst one. This range can be set in the option. Ga stands for the absolute gain. Gh is simply derived by substituting 2.15dB from Ga. Gh is not displayed if you include the ground option. MMANA-GAL does not thoroughly consider the effective digit numbers. The impedance is shown with many digits, but it just is for preserving the effective digits. This is important particularly for low impedance. You should keep in mind that it would include practical inaccuracy. If you want to simulate two or more media`s grounds, you have to input the X-distance or R-radius and height parameters as well. MININEC has an option that takes account of the virtual ground screen, MMANA-GAL follows it. Media is referred only to in the calculation of the far electric field (beam pattern). Set the dielectric constant and conductivity (mS/m) that reflect the ground condition. The height of the first media should be = 0. Dielectric constant and conductivity of the ground
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