Fadhel Ghannouchi

The wireless and satellite communications communities have always been looking for power- and spectrum-efficient amplification systems. The design of such power amplifiers has to be considered closely together with the system architecture in order to ensure optimal system level performances in terms of linearity and power efficiency. This implies the use of adequate transmitter’s architectures that convert the analog base band information to architecture dependent amplifier driving signals such as sigma-delta, EE&R, and LINC architectures. This seminar lays out the principles behind the software enabled linear and highly efficient power amplifiers/transmitters sub-systems. Design and practical realization of RF/DSP co-designed transmitters for MC-CDMA and OFDM wireless applications will be presented.

This talk briefly presents the basic concepts of linearization technology as well as the reason why linearization is being considered as an enabling technology for 3G and beyond wireless communication systems, Included will be the description and explanation and how linearization favorably affects both spectrum and power efficiencies of transceivers and what are the devices the system based techniques available to the designer of nonlinear communication circuits and systems. Feedback, feed forward and predistortion based linearization techniques will be presented. Important and critical issues in designing these linearizers will be discussed in light of the broadband communications applications targeted either for handheld or base station terminals. Examples of analog, digital, or hybrid implementations will be presented and discussed.