System control and simulation for adaptive 2-200 MHz multiple mechanism radio communication

Multiple Mechanism Propagation Paths (MMPPs) are said to exist if information is transferred between communications system terminals via a number of distinctly different physical processes. Such multiple mechanisms may co-exist on a common frequency channel to varying extents, or on a number of separate channels. In both cases the occurrence of such mechanisms will be time-variable. MMPPs can be regarded as potential noise sources, giving rise to fading, inter-symbol interference, etc., and yet also as having exploitation potential, offering improved system performance. In order to both mitigate the deleterious effects of simultaneous MMPP occurrence on a single channel, and have the facility to exploit their potential, a flexible and adaptive system architecture is required. This paper reviews the design of a radio communication system which utilises all propagation mechanisms in the frequency range 2-200 MHz. The success of the system relies on its ability to adapt to the prevailing propagation mechanisms and thus the design of control algorithms utilising embedded RTCE (real-time channel evaluation) is of critical importance. The paper also reviews propagation simulation methods implemented to aid the system development, including a model of the tropospheric reflection mode