Polar-loop transmitter

A new approach to the design of s.s.b. transmitters, which overcomes the problems of the present-day transmitters, is proposed. This is based on the generation of r.f. energy at channel frequency and the use of a feedback control system to regulate the output spectrum of the transmitter so that it approximates arbitrarily closely to that of a low-level s.s.b. signal generated in a conventional way. The principles of design are applicable to all frequencies and power levels, and also readily adaptable to other modes of modulation.