KOUASSI , Boris

Spatial interweave cognitive radio opportunistically exploits spatial holes to enable transmission of secondary systems. The latter form carefully aligned spatial beams so that there is no interference to the primary system. This requires acquisition of the (spatio-temporal) channel state (CS) between the secondary emitter and the primary...

Cognitive radio (CR) aims at enabling the coexistence between legacy systems called primary users (PU) and secondary users (SU), provided the SU do not (significantly) cause interference on PU links. Massive MIMO systems on the other hand yield significant performance and reliability enhancement. In this paper, we investigate the capacity of...

The channel reciprocity is an advantageous hypothesis in cognitive radio (CR) technologies, however it is not practically exploitable due to miscellaneous discrepancies including the radio frequency (RF) impairments. Consequently, previous studies proposed calibration solutions to solve these RF impairments. This paper is a step ahead in the...

LTE the latest mobile network standard, is widely adopted and targets high spectral efficiency. Cognitive radio (CR) systems on the other hand enable smart use of wireless resources leading to significant performance and reliability improvement. Accordingly, adopting the LTE specifications in CR it is a reasonable choice to optimized the...

LTE the latest mobile network standard, is widely adopted and targets high spectral efficiency. Cognitive radio (CR) systems on the other hand enable smart use of wireless resources leading to significant performance and reliability improvement. Accordingly, adopting the LTE specifications in CR it is a reasonable choice to optimized the...

In Cognitive Radio (CR) systems, primary licensed and secondary unlicensed users share the same spectrum. To minimize the interference caused by secondary users to primary users, we use Beamforming (BF). To perform BF in time division duplex (TDD), we acquire Channel State Information (CSI) with the help of channel reciprocity. This reciprocity...

We study the problem of beamforming design for a Cognitive Radio (CR) system in which a multiple-input multiple-output (MIMO) link, identified as secondary link, wants to opportunistically communicate without harming a licensed MIMO system, called primary. In the proposed solution the opportunistic user designs its beamformer in order to span...

Cognitive radio, which enables smart use of wireless resources, is a key ingredient to achieve high spectral efficiency. LTE, the latest evolution of cellular standards, is widely adopted and also targets high spectral efficiency. Hence, to enable wide adoption of cognitive radio, using LTE as the physical layer is a natural choice. Targeting a...