Feedback Framework in Multiuser MIMO Systems

Computing & Wireless : Wireless and Communications

Available for non-exclusive licensing

Inventors

  • Robert Heath, Jr., Ph.D. , Electrical and Computer Engineering
  • Sunghyun Cho , Samsung Advanced Institute of Technology
  • Taiwen Tang, Ph.D. , Electrical and Computer Engineering
  • Sangboh Yun, Ph.D. , Samsung Advanced Institute of Technology

Background/unmet need

Cellular wireless communication networks support the transmission of data between the base station and multiple users. In such systems that support high-speed data transmission, the link from the base station to the mobile system requires high capacity. One mechanism to improve throughput is to schedule transmissions to users based in part on their channel state information. This method, known as multiuser diversity, sends data to users when their channel conditions are good. Unfortunately, acquiring feedback from multiple users takes system resources away from the uplink channel. Thus, in practice, acquiring channel state information for many users is difficult to perform.

Invention Description

We propose a solution for improved network performance by creating a system and method for enabling a reduction in the amount of feedback required for scheduling in multiuser environments. The invention consists in part of optimizing the feedback mechanism based on the channel state information. This allows the system functionality to be improved when there are few users in the system, and feedback is not a problem, as well as when there are many users in the system, when feedback is a problem. We also propose a new set of protocols for sending feedback information. Specifically, we propose a new random access protocol that enables the channel state information of multiple users to be acquired quickly and efficiently by the base station.

Benefits/Advantages

  • Provides a means to obtain channel state information from multiple users in a cellular system
  • Improves system throughput and capacity
  • Works with advanced communication technologies such as MIMO and OFDM

Features

  • New random access protocol that enables the channel state information of multiple users to be acquired quickly and efficiently by the base station
  • Described in the context of a MIMO (multiple-input multiple-output) communication system but can be specialized to single antenna communication systems as well
  • Uses feedback controllers to limit the amount of feedback data required from each user

Market potential/applications

This invention can be directly applied to existing/future cellular systems and wireless LAN.

Development Stage

Proof of concept

IP Status

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