<p>We use a full-wave approach to find the field of monochromatic whistler waves which are excited and propagating in the low nighttime ionosphere. The source current is located in the horizontal plane and can have arbitrary distribution over horizontal coordinates. The ground-based horizontal magnetic field and electric field at 125 km are calculated. The character of wave polarization on the ground surface is investigated. The percentages of source energy supplied to the Earth-ionosphere waveguide and carried upward ionosphere are estimated. Received results are important for the analysis of ELF/VLF emission phenomena observed both on the satellites and on the ground.</p>