Diversity Telephone Receiving System of R.C.A. Communications, Inc.

Difficulties encountered in the reception of high-frequency radio-telephone signals are described: the chief of these being fading and noise. General methods of solving these difficulties are discussed and the most desirable ones pointed out. The utilization of space diversity of fading is then taken up and methods of applying this principle to the reception of telephone signals are discussed. This method chosen is next described, with reasons for the choice and explanation of the circuits and action of the system. A description of the general features of the equipment is given, and this is followed by a detailed consideration of the individual units comprising the double detection receivers and the combining and control equipment. Over-all characteristics are then given of selectivity and fidelity and a statement of sensitivity and minimum signal strength for commercial service. Improvement obtained by the use of this system is discussed, and the uses to which it is being put are stated. The latter include international rebroadcasting and transoceanic telephone service.