Fadhel Ghannouchi

Start Year 2009

Fellow IEEE and Fellow IET

CORE Professor and Senior Canada Research Chair,

Director, iRadio Laboratory (www.ucalgary.ca)

Department of Electrical and Computer Engineering Schulich School of Engineering,

University of Calgary, Canada

FGhannouchi (at) IEEE.Org

SDR Based Power amplifiers /Transmitters for Advanced Wireless and Satellite Communications

The next wave in the information revolution will consist of bringing intelligence to the information and communication technology (ICT) sector, allowing seamless and intelligent networking and communication between different users using different services and operators. This will lead to the convergence of communication technologies, aiming at the development and deployment of cooperative and ubiquitous networks that involve existing and future wireless and satellite communications systems.

A critical element in enabling the convergence of different communication systems is the development of software defined radio (SDR) systems that can be used across different frequency bands and for multi-standard applications. This SDR has to be developed to support different frequency carriers and modulations schemes concurrently, in addition to being power- and spectrum-efficient, in order to be able handle high data rates, while being less energy-hungry and more environmentally friendly.

The design of power amplifiers as critical components in any SRD based communication terminal 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 architectures that convert the analog baseband information to architecture dependent amplifier driving signals, such as sigma-delta, EE&R, Polar and LINC architectures. This talk lays out the principles behind SDR systems and examines the design of software-enabled linear and highly efficient RF/DSP co-designed power amplifiers/transmitters for multi-standard and multi-band applications.  Recent advances and practical realizations will also be presented and discussed.

Linus Maurer

DICE, Linz, Austria

Freist?dter Strasse 400

A-4040 Linz
Phone: +43 5 1777 15138
Fax: +43 (4242) 3020 7602

linus.maurer (at) infineon.com

Highly Flexible Digital Front-End Enhanced CMOS-Based RF Transceivers

State-of-the-art RF transceivers are mainly optimized for a single radio access technology and do rarely employ digital signal processing capabilities on the RFIC. Digital functions are commonly focused on control interfaces (e.g. for PLL programming) and calibration functionality (e.g. for analog filter tuning). Since analog blocks are not well suited for reconfiguration by the nature of their implementation such transceivers will not be able to effectively tackle upcoming challenges in terms of flexibility arising with the need of multi-system/multi-mode/multi-band operation.

The lecture will focus on the practical realization of an advancement of the well-known direct conversion receiver and transmitter architectures: digital signal processing functions are incorporated directly onto the RFIC to increase its flexibility. The digital front-end (DFE) closes the gap between traditional base-band processing done at the MODEM-IC and the high data rates at the output of the analog to digital converter (ADC). The proposed DFE implementation realizes traditionally analog functions (e.g. channel selection filtering, DC-offset compensation, etc.) by providing highly configurable filter blocks, which are adapted to the respective standard requirements. Furthermore, the DFE can be used to efficiently optimize the overall signal path, e.g. by correcting analog imperfections in the digital domain. Consequently, the traditionally analog data interface between RFIC and MODEM-IC is replaced by a digital one. With the advent of RF-CMOS the implementation of the DFE locally on the RFIC has become technically feasible and also economically reasonable. Furthermore, Realizing digital signal processing functionality on the RFIC in an advanced CMOS technology for mass market applications has advantages over "pure analog" RFICs in terms of production stability, power consumption and cost.

Alessandro Cidronali

Univ. Firenze, Italy

Green Wireless Technology

The explosion of wireless connectivity for data, voice and multimedia contents has determined a pervasive growth of heterogeneous networks that provides continuous maximum potential performance. At present, the absence of a real time cross-layer resource management strategy makes the wireless network operate at its almost maximum power level, regardless of the user real estate and needs. Thus the wireless network should be capable to reconfigure its parameters as a function of the actual users’ demand, in terms of quality of the signal and quantity of the channels (number of users).

Recently strategies capable to track the traffic and then make the single base station able to decide whether to switch itself on\off or modulate its output power level have been introduced. The challenge consists in making this operation consistent with the overall network efficiency: it doesn’t make sense to increase the complexity over a given level if this will increase power consumption or if some part of the whole network is driven in an inefficient state. An enabler technology consists of a wireless front-end capable of maintaining high level of efficiency over a broad band and for peak power that might be adjusted according with the network requirements.

This talk focuses the issues related to the energy efficiency through a wireless network, analyzing the strategies and technologies capable to reduce the entire power budget while preserving the interconnectivity, beyond the consolidated paradigm of efficient RF PA design.