Signal fading data at L band /1.5GHz/ due to multipath reflections from the sea

Information on the multipath phenomenon due to sea reflections of the radiowave is required in connection with the planning of a Maritime Mobile-Satellite Service. Under calm sea conditions and particularly at elevation angles up to about 10 degrees the component of the satellite signal reflected by the sea and received by a ship's antenna can be significant compared with the direct signal. The resultant received signal will then show a degree of fading with respect to time which may cause severe deterioration of the communication link. An investigation was in this connection conducted to investigate this multipath phenomenon. Use was made of the transit of the Applications Technology Satellite (ATS-6) between 94 deg W and 35 deg E. Attention is given to the experimental procedure, details of digital processing, the determination of the sea state statistics, and a multipath fading prediction by computer modelling.