Simplified equalization scheme for distributed resource allocation in multi-carrier systems
AssigneeNXP B.V.
InventorsXiabo Zhang, Ni Ma
Life of this patent
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Abstract
In multi-carrier systems, distributed resource allocation of the resources of multiple user equipments (UEs) can result in better frequency diversity gain but can also induce Inter-Carrier Interference (ICI) between UEs. This ICI can become quite serious in a high mobility environment. Based on a novel radio channel model for ICI cancellation in multi-carrier systems and an iterative channel estimation scheme for ICI cancellation in multi-carrier systems, the present invention provides a simplified equalization scheme in the frequency domain to determine and remove ICI of both a targeting UE as well as other UEs.
Claims16
An equalization method for distributed resource allocation in multi-carrier systems having a plurality of user equipment (UEs), comprising:
- providing a channel estimation module configured for obtaining a channel feature matrix including channel parameters and a matrix that characterizes inter-carrier interference (ICI) coming from the plurality of UEs;
- using the channel estimation module for defining a channel model wherein received signals are described as a product of transmitted signals with the channel feature matrix that includes channel parameters and a matrix that characterizes the ICI coming from the plurality of UEs, wherein the channel estimation module is used in an iterative estimation process including iterative linear channel estimation;
- obtaining the channel feature matrix including the channel parameters and ICI by using the channel estimation module as part of an estimation process that is based on the defined channel model;
- using an inversion module for an inverting sum of the channel feature matrix plus the matrix that characterizes the ICI coming from the plurality of UEs, and therein providing an inverted channel response matrix;
- and
- performing channel equalization.
An equalization system for distributed resource allocation in multi-carrier systems having a plurality of user equipment (UEs), comprising:
- channel estimation means for obtaining a channel feature matrix A, comprising channel parameters, and a matrix B characterizing an inter-carrier interference (ICI) coming from the plurality of UEs such that received signals are Y=(A+B) X;
- means for inverting the matrix A+B to obtain (A+B)−1 using A−1 and the equation
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An equalization system for distributed resource allocation in multi-carrier systems having a plurality of user equipment (UEs), comprising:
- a channel estimation module for obtaining a channel feature matrix A, comprising channel parameters, and a matrix B characterizing the ICI coming from the plurality of UEs such that received signals are Y=(A+B) X;
- a simplified module for inverting the matrix A+B to obtain (A+B)−1 using A−1 and the equation
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- a channel equalization module to perform equalization according to an equalization algorithm using the inverted channel feature matrix A−1 to estimate the transmitted signals X=f((A+B)−1) Y.
Dependencies are inferred from the claim text.