Reflection properties of the lower polar ionosphere, and features of the excitation and propagation of superlong waves (SLW) at high latitudes (review)

A brief characterization is presented of the sources of anomalous ionization in the lower ionosphere at high latitudes is examined. Some new results concerning the measurement of electron density at high latitude in the lower ionosphere obtained by various methods are reviewed. A summary of results is presented of the effective heights (in km) obtained at moderate latitudes and in the polar cap by means of both monochromatic and pulsed SLW probing. The properties of SLW propagation in the polar region are discussed. Transpolar SLW propagation and a local experiment are reviewed