Research – Riccardo Raheli

Interests

• Information and Communication Technology
• Communication systems and networks
• Storage systems and networks
• Signal and information processing

Selected Research Results

• Media noise affecting data storage systems is not just noise but a useful signal component which can be properly exploited, as shown in the papers by R. Pighi (TMAG 2006). One of these papers received the "2006 Best Student Paper Award in Signal Processing & Coding for Data Storage" from the IEEE Communications Society
• Typical impairments of optical communications systems, such as chromatic dispersion, can be effectively coped with in the electrical domain, after a direct photodetector. In fact, the information loss entailed by this nonlinear device is limited, as shown in the papers by M. Franceschini (EL 2006 and JLT 2007)
• MAP symbol and sequence detection (achieving minimum symbol and sequence error probability, respectively) can be based on identical branch metrics for any system with finite memory, as shown in the paper by G. Ferrari (JSAC 2005). Relevant results also appear in an invited paper published in the prestigiuous Proceedings of the IEEE 2007
• Universality of LDPC codes for memoryless channels. The convergence mutual information threshold is largely invariant to the channel characteristics for a wide set of memoryless channel models, as shown in the paper by M. Franceschini (TCOM 2006)
  
• An LDPC code can be propery designed to be effective in a channel with memory, such as one including a differential encoder or impaired by ISI. Relevant results appear in the paper by M. Franceschini (JSAC 2005)
  
• If spectrum is of minor concern, a nonlinear power amplifier can be operated in strong saturation to achieve an appreciable SNR gain. A good receiver is needed, though. Relevant results appear in the paper by A. Vannucci (TCOM 2002)
• Noncoherent (or multiple differential) sequence detection. Relevant results appear in the papers by G. Colavolpe (TCOM 1999)
• Per-Survivor Processing. Relevant results appear in the papers by R. Raheli (TCOM 1995 and TCOM 1996)
  

Awards

• 2006 Best Student Paper Award in Signal Processing & Coding for Data Storage from the IEEE Communications Society
  

Membership in Professional Societies

• Institute of Electrical and Electronics Engineers (IEEE), since 1987
• Communications Society of the IEEE, since 1987
• Information Theory Society of the IEEE, since 1991