The Phase-Shift Method of Single-Sideband Signal Generation

A general expression is developed for sideband suppression obtained with the phase-shift method of single-sideband signal generation. The sideband suppression ratio is expressed in terms of four systems parameters, three of which are governed by the characteristics of wide-band phase-shift networks employed in such signal generators. Several typical phase-shift network configurations are analyzed and shown to be equivalent to a cascade of networks of "simplest" type. In addition, certain special network combinations are presented. A simple dual-channel multiplex single-sideband generator of the phase-shift type is shown. Use of the phase-shift method in combination with band-pass filters to enhance system performance is discussed. The role of a modified phase-shift type of signal generator as a system-test signal source is outlined. The eflects of intermodulation distortion on signal purity and the performance stability of the phase-shift method are discussed from the system viewpoint.