Perlaza at TU-Berlin talking “On the Benefits of Feedback in Wireless Communications”

Invitation to a talk by Dr. Samir M. Perlaza (INRIA, France)

ABSTRACT:

In this talk, the key role of feedback is highlighted in two fundamental problems: (a) interference management in wireless networks; and  (b) simultaneous wireless energy and information transmission. In the former, channel-output feedback is shown to be instrumental in increasing the capacity of the Gaussian interference channel due to the fact that it induces a kind of transmitter cooperation. Interestingly, this cooperation appears naturally given the broadcast nature of wireless channels independently of whether or not transmitters intend to cooperate. Thus, despite the nature of the network, i.e., centralized or decentralized, there always exists a non-negligible benefit when using channel output feedback. In the latter, channel-output feedback is shown to be beneficial when several transmitters intend to transmit information to a destination and energy to an energy harvester. In this case, also known as multiple access channel with energy harvester, all information and energy rates that are achievable are fully described with and without feedback. In the centralized case, channel-output feedback can at most double the energy rate given a fixed information rate. In the decentralized case, depending on the decoding scheme at the receiver, channel-output feedback allows the achievability of some Pareto optimal network equilibrium operating points.