The Problems of Transition to Single-Sideband Techniques in Aeronautical Communications

The use of SSB techniques in air-ground communications appears highly desirable because of the spectrum conservation and because of the improved performance which can be achieved under the limitations on size and weight or peak antenna voltage. An orderly and economically sound procedure of transition from AM to SSB techniques requires that a degree of compatibility between the two systems be achieved. Early SSB equipments must be capable of operating in an AM system, and eventually AM equipments will have to be modified to perform in an SSB system. Various techniques for effecting both types of modifications are reviewed. It is suggested that new SSB equipment provide an AM detector and means for transmitting a full-carrier SSB signal which can be received on an AM receiver.