Title: A Switched-Capacitor DSB to SSB Conversion Using a Recursive Hilbert Transformer
Author: José Gabriel Rodríguez Carneiro Gomes
Advisor: Antonio Petraglia


    A new implementation of a complete double-sided band/single-sided band (DSB/SSB) converter using switched-capacitor techniques is proposed in this work. Since one of the DSB signal sidebands is suppressed, the corresponding SSB signal can be decimated by two without loss of information. By using a recursive Hilbert Transformer to implement efficient SSB modulation, an image rejection ratio (IRR) above 40 dB over the suppressed sideband can be achieved. The design of the Hilbert Transformer through structurally allpass transfer functions renders the system a good dynamic range and very low sensitivity to errors in capacitance ratios implementing the coefficients.

    Some systems that are commonly used for modulation and demodulation are analyzed. The prototype of a complete DSB to SSB converter has been built using discrete components, and the obtained experimental results are shown. Finally, some considerations are sketched concerning the DSB to SSB converter monolithic implementation using conventional CMOS integration processes.