Automatic microprocessor-based receivers for the decca navigator system

The paper deals with the design principles of a type of microprocessor-based receiver for the Decca Navigator continuous-wave, hyperbolic radio-navigation system. Two experimental receivers are described, one for automatic vehicle location, the other hand-portable. Both are fully automatic in operation. Novel features of their hardware software are outlined and the results of land-vehicle, marine, airborne and hand-held field trials are presented. The results demonstrate that, although the receivers are small, light, cheap to manufacture and low in power consumption, their accuracy, fix repeatability and skywave interference sensitivity compare favourably with those of traditional analogue receivers.