Reliability for digital HF radiocommunications systems

A new method is described for the calculation of basic circuit reliability (BCR) for digital HF radio systems as an extension to the technique in international use for analogue systems. In this method, besides considerations of signal/noise ratio, allowance is also made for time and frequency dispersions. First-order models are presented to show the likely dispersions encountered and with user-specified requirements of minimum necessary signal/noise ratio and maximum tolerable dispersions, BCR may be estimated for specific scenarios of interest. Sample calculations show the dominant influence that dispersion can have on a digital system´s performance. A strong plea is made for the collection of additional observational data to permit model refinement