Most of the information about the near-Earth's environment up to the height of the F region maximum is obtained by ionosondes. The height range in question is below the altitude of long-lasting satellites. In addition, satellite measurements cannot provide the temporal and spatial resolution for an unambiguous sampling of the dynamic phenomena of the ionosphere, unless a large number of satellites with identical equipment are placed in proper orbits. Similar remarks apply to balloon and rocket observations. The advance of digital ionosondes permits the measurement of new quantities (for example, echo phase) and of classical parameters (for example, delay time and signal strength of an echo) with much improved precision. The analysis of such data in turn provides more details and higher accuracy of properties of the ionosphere. This will be demonstrated here for electron density profile parameters, Doppler frequencies, angle of arrival measurements, and other quantities.