Séminaire ICI : Megumi Kaneko

Titre du séminaire et oratrice

Contention-based Uplink CSI Feedback with Variable Collision Protection for a Cellular Multi-Carrier System.
Megumi Kaneko, Kyoto University.

Date et lieu

Mardi 12 juin à 14:00.
ENSEA, Cergy-Pontoise, salle 384 (plan d'accès à l'ENSEA).


The optimization of the Downlink (DL) resource allocation in Multi-Carrier (MC)-based wireless systems requires the feedback of the Channel State Information (CSI) for each user/subchannel to the Base Station (BS), consuming a high amount of Uplink (UL) radio resources. To alleviate this problem, several works have considered contention-based CSI feedback, where users attempt to randomly access the UL control channel, experiencing collisions.

In this talk, we propose a feedback scheme based on the idea of variable collision protection, where the probability that a feedback information experiences a collision depends on its importance. By partitioning the CSI into orthogonal layers of priority, and allocating different numbers of feedback slots to each layer, this scheme ensures that the feedback success probability is higher for the CSI with better quality, which is more likely to be used by the scheduler. Furthermore, we present a theoretical performance analysis of the proposed scheme, assuming Maximum CSI (Max CSI) and normalized Proportional Fair Scheduler (PFS), where a tight approximation of the achievable throughput is obtained assuming discrete Adaptive Modulation (AM) and CSI feedback which are relevant for practical systems. Analytical and simulation results show that our proposed scheme provides an excellent trade-off between system performance and feedback overhead.