HF SChEMe: a skywave channel error model

Simulation has been extensively employed to evaluate concepts included in the current generation of automatic link establishment (ALE) high-frequency (HF) radio systems. As development of HF automation proceeds from link-layer technology to network- and higher-layer technology, it is no longer necessary to devote great amounts of computer time to detailed simulation of the physical medium. Instead, the error behavior of the medium should be abstracted so that simulation resources may be concentrated on the phenomena of interest at these higher protocol layers. In this paper, a model of channel error behavior is derived that accurately captures the operation of the ALE modem operating over Gaussian noise and skywave channels. When this model is employed in place of detailed simulation of the modem and channel, an overall simulation speedup of two orders of magnitude results