Inverse Ionosphere

The distortion introduced into a long-range communication system by unpredictable multipath conditions of the ionosphere is described in this paper. A device to eliminate this particular form of distortion is then described, using a sensing technique, a logical matrix, and a signal restoration network. Since both the multipath model of the ionosphere and the restoration network are linear, the principles of superposition apply to the cascaded combination so that the described technique is generally applicable to all waveforms. Specific restoration networks are described for several typical ionosphere multipath conditions. The effects of white noise upon the correction network and the signal are noted. The inverse instrumentation can be placed in the system either as a restoration network at the receiver or as a pre-distorting network at the transmitter.