The application of the asymmetric polyphase filter in an SSB transceiver

This paper describes the polyphase phase shift filter system of SSB generation and demodulation, and highlights the suitability of the polyphase filter for interfacing with CMOS analogue gates as a switching mixer. The performance is analyzed in the light of several years of production of a 1.6 to 30 MHz 100 W transceiver using this technique. Typically under conditions of power amplification the apparent carrier and sideband suppressions are reduced from the levels generated in the modulator. The reasons for this degradation in performance are presented